We got my shop infloor heat hooked up and finally going this winter, I've talked to all the experts on heating demands for it and according to everyone of them my current owb should do it, now that said this winter is extremely cold and windy but we're having problems getting enough heat out of the owb to keep up. I've run the calculations myself and it depends on who's calculator figures you use, the shop is 32x80, that portion has 20 foot ceilings in it, along with a heated service pit that's 3 foot wide by 7 feet deep by 50 foot long, and another office that's 15 foot square with 8 foot ceilings. The office is cement block with granular insulation that you pour into the blocks as its built, can't recall the exact name, it comes in sacks you can still buy at menards as a pour in insulation. I know that's not idea but its how it was built, this is a remodel job on an existing building. The rest of the shop is also insulated, almost 8 inches of blow in for the walls and over a foot in the ceiling, my large door only has 4 inches of fiberglass in that cavity. Everything in the shop is in floor heat, the cement is right at 8 inches thick, some the tubes are in the middle of the concrete tied to the rebar, the rest is stapled to the insulation under the concrete.
Some tell me to use a calculation for the square footage, others tell me I need to figure cubic feet for a more realistic figure. We're also heating an old farmhouse that's really well insulated and has descent windows in it, that is a two story house with a full basement under it that's not finished, but the two floors we do live on are about 2000 square feet or about a 1000 a level. We also heat the hot water in the house
Right now we're running a wood doctor the second to the largest model they made, we fill it three or four times in 24 hours and the fan never shuts off, if the wind doesn't blow and its not much below zero, we can keep up, if the wind blows or its really cold, like we've been having this winter of -20 below plus wind chills, the shops slightly above freezing and the house is barely 70 degree's. On mild days the shop gets back up to about 40 degree's. I was hoping on 55 for the shop all winter long and about 75 in the house on the main floor, and upper 60's on the second floor.
I live in northern Iowa and am thinking about going to a larger owb, but with the cost of them, everyone's is the ideal unit and big enough to handle this easily, I'd like opinions on what others think I need not a salespersons opinion, I'd rather not find out again, my next furnace won't keep up either. The calculations I came up with were in the neighborhood of 750,000 btu's, then add in the efficiency factor of X of the owb and it gets up close to a million btu's. I've used another btu calculator and came up with under 400,000 btu's if you figure on square footage and not cubic footage.
Any suggestions or opinions?
I've often wondered if sizing one large enough OWB is the best way to go, rather than having two and maybe three smaller OWB's to share the load.
Seems your example is a good one for such consideration as all winters likely will not be like this one, and the load is not equal for the full heating season.
In addition, those heating DHW year around would not need the full capacity of one OWB sized for the winter season.
A lot of things to figure in, and not something I need as my indoor unit is sized perfect for my needs.
But in reading about other applications on the forum, I can't help but wonder.
Beenthere, from my past experience on heating hot water in the summer, we were using from a 1/3 to almost half the wood it took to heat the entire house in the winter months, we did this last summer and I ran out of wood in mid january this year, and have to be cutting wood and directly burning non seasoned wood, also adding to the my problem of keeping up. From my calculations, with the pumps I have installed in the system, to heat hot water, for only a few people now verses all we had before in the house, the electrical consumption was about what my electric bill would be to heat the hot water, and I save all the wood for the winter.
We've thought about going to a wood chip furnace in the past but to size one for the load was about impossible, I might have to rethink having more than one furnace in the system and one burning wood chip and the other firewood.
To have anything more than two in the system, would not save much, I'd need a couple pumps more per furnace to run constantly to keep the systems from freezing and to keep everything up to temp. But you do bring up a very good point, anyone have experience with two or more owb's per system, would I then need a hot water storage someplace and then just kick in each furnace as its needed to maintain temps?
At this point I'd entertain any and all ideas, I've been focusing on one large unit but maybe two equally sized one's might be the way to go, anyone have experience with this?
Randy, what kind of temperature drops and GPMs do you see across the loops of the infloor.
OK, few more questions about shop;
How much insulation under slab?
What kind of loop length and pipe size? if known
How many loops and or zones are in shop?
Also how often to garage doors get opened?
Only reasons I ask these questions is I live in EC Minnesota, and run about 7000sf total between two building (48'x80' garge with 12' ceiling and a 3000sf house), with a CB eClassic 2400 (gasser) and its rated at a MAX of 250k btu/hr and I am able to keep up except that week it was -20s and -30s. I do have to feed the OWB several times a day, but my choosing; if I where to jam firebox full on a -20 day guessing that I would see a burn time of 10-14 hours
Heat lines are half inch, each run is 300 feet or less, some had to be roughly 265 to come out, there are 8 loops in the main shop, two more in the office, we hooked them to different zones for priority in shop, two zones and pumps in the shop and one for the office, there is the two inch thick insulation board under the entire floor everywhere, but we put pylasters on the pit walls, and those are hooked directly into the floor slab, but those pylasters and pit walls have insulation board all around them before we backfilled, not an ideal setup but was the best we could do to get strength we needed to support the pit walls.
We've used a temp gun to get direct readings off the floor, the incoming floor lines are about ten degree's warmer than the outgoing lines on each loop, unless it really cold, then we're having trouble keeping the temps high enough on the incoming loop lines to even maintain temps, which takes forever to gain back once the winds and bitter cold weather subsides. If we could get the water to maintain a constant temp out of the furnace we could keep the floors warm, this winter, its taking so much to maintain the temps, the floors cool off and its a losing battle, in the office we added electric heaters, due to freezing temps on the water system, the waterline, toilet and sink froze one night, with -60 wind chills.
As for opening the door, its full width of the shop, or 32 by 20 foot tall one piece hydraulic door, we open it several times a week, more if I'd ever get the shop warmed up enough to use it much, then maybe every day in the evening, but seldom open it all the way, just enough to get equipment in and out usually skid steers and trucks, is open less than a couple minutes at one time ever.
Right now, we're filling the furnace in the morning, mid morning, mid afternoon, late evening and again about 4 am, the blower never shuts off and the water temps never get high enough to allow it to kick off, in the really bitterly cold windy days where it got down to -60 below wind chills, we were filling it or adding to it, every four hours around the clock. All the lines are below ground to and from the furnace, in the insulated pex lines, two per four inch tile foamed in, not much water temp drop to and from the buildings on those lines. Its the wind this year that sucks the heat out of everything, not the frigid temps as much.
When it warms up outside, and wind does die down, everything gets back to normal again and keeps up, but it takes days if not more to warm the shop floor back up, and before then we are down in the deep freeze or the wind kicks up again and we start all over again. In the fall we had the shop warmed up to about 65 degree's and everything was working like clock work, then the cold kicked in big time and its been a losing battle ever since. We keep the temps in the house up by slowing the circulation pump in the shop somewhat, otherwise we'd have to kick in the lp furnace in the house instead to keep that warm. I'd eventually like to add an attached garage onto the house and put infloor heat in that as well, there's no way this furnace can handle anything more, can't even handle what we have on it now, unless the bitter cold and wind never come back.
Do you have temp gauges on the outflow and inflow lines? Many radiant heat systems require a re-entry loop (sorry, I don't know what the correct plumbing term is) to lower the temp of the hot water down to about 125 degrees before entering the flooring system. My understanding is that really hot temps can crack the concrete. Do you have such a system design?
While others have been very successful with radiant heat supplied from an OWB, it is the use of the return loop through a mixing valve to purposely lower the water temp in the flooring that makes me question its effectiveness in large systems like yours.
I'll try to explain my thinking and then those with more knowledge and experience can correct me.
It's takes a TON of energy to bring a large, concrete slab up to temperature. When that slab is in contact with a large, cool air mass, it loses heat faster than in a more controlled environment like a home, with lower ceilings, rugs, etc. Yet most radiant heat systems purposefully decrease the temp of the return water to the OWB, making it work it's tail off. Most domestic OWB's with a heat exchanger have a return water temp in the (guessing) 160-170 degree range. So the OWB only has to raise it 20-30 degrees. In the standard home, the volume of returned water to the stove compared to the volume capacity of the OWB, expressed as a percentage of the OWB water capacity, is usually pretty small. In a large system like yours, the percentage of water that's cooling in your radiant loops (compared to the volume of your OWB) is much greater than in the standard home use, further demanding the OWB to work harder. The return temp from radiant flooring is 110-120 degrees (again, guessing), so the amount of energy needed is significantly more than in normal home heat exchanger use, and the volume of water needed to have that increase in temperature is much greater, so I can see how an OWB would have difficulty keeping up.
I understand that, once the radiant floor is up to temp, it holds heat very well, like the stones of a fireplace with a wood stove burning all night. But if the air above that flooring is cold, and the volume of air is large enough that it requires a lot of energy to have the air temp increased, then the flooring will be asking for energy all the time, and you will not see your OWB cycle off, as is expected.
Long ago, when I was a nicky-new-guy to the Forum and to OWB's, I made a comment that, in certain situations, OWB's may not be a great source of heat for radiant heat systems. I received some differences of opinion then, and I'm sure I get some more now. But, if the energy demands of the radiant heat system are extremely large, and the system cools the return water to the OWB to protect the flooring construct, then I think that there's a tipping point at which radiant heat may not be the best solution for heat in that space. From the sounds of it, the only solutions are, 1) Put the shop in a warmer climate ;), 2) Enjoy working in the cold ;) :o, 3) Increase the temp in the flooring (adjust the return loop flow) so that more energy enters the system. This should increase the temp of the return water to the OWB and ease its burden. Or 4) Get a larger heat source. How much wood are you using now? I can only imagine.
OK, friends, tell me where I'm off kilter. Best of luck, Randy.
I have been playing with your numbers. 80 x 32 = 2560 sq. ft If you are getting 30 btu's of heat per sq. ft {and that's a lot} = 76,800 btus per hour delivered into the building. That is enough to heat the building in cold weather but not frigid conditions. I have come up with # around 300,000 btus and up for the garage. The garage needs supplemental heat but you can not get it from the boiler you have.
You could look into 2000 gallons of storage to help get thru the cold spells [ around 1,750,000 btus] 12 hours of storage.
You may be a good candidate for a Garn boiler in your shop. I believe the commercial unit holds 3200 gallons 700,000 btu's
Ps my math could be wrong. Your situation is challenging
I could be wrong, but if the wind is taking such a large toll, I'd say you have a pretty large air leak somewhere in that building. I'd look at temporarily adding weatherstripping to that big door and see if that helps. A draft in that large of a space would be impossible to battle. Just my two cents.
your water temp going into the floor should be around 170 deg. it wont hurt the concrete at all. been doing that temp in crete for 20 yrs no problems.if your pumps are going to slow to much water temp is removed, thus return temp to low for the stove to re heat .
Quote from: red oaks lumber on February 13, 2014, 11:46:49 AM
your water temp going into the floor should be around 170 deg.
COMPLETELY DISAGREE, water going into a slab should never exceed 150f - that is WICKED hot for a slab and you run the chance of concrete wanting to crack and fall apart.
With the 8" slab you are talk about 100+ tons of concrete so reaction time will be increase on initial start-up (4000sf garage takes a full day to get up to temp in fall). That being said openig and closing a door even a HUGE one like yours, if the slab was up to temp recovery woudl be instant once door is shut.
Quote from: Holmes on February 13, 2014, 11:19:04 AM
I have been playing with your numbers. 80 x 32 = 2560 sq. ft If you are getting 30 btu's of heat per sq. ft {and that's a lot} = 76,800 btus per hour delivered into the building. That is enough to heat the building in cold weather but not frigid conditions. I have come up with # around 300,000 btus and up for the garage. The garage needs supplemental heat but you can not get it from the boiler you have.
Assuming SNOWMELT conditions (150btu/sf), for garge 32'x80' = 2560sf +15'x15' = 2785sf x 150btu/sf = about 400k BTU/hr
Little John Minnesota , are you in John Barba's territory?
In my shop we totally isolated those systems with in floor heat, we put in a heat exchanger on a hot water heater, and have a circulation pump installed in that to kick in when the temp inside the water heater gets below 120 degree's and reheats the water inside the heater, the floor loops are taken off the water heater and that entire system is pressurized which is really nice, we used anti-freeze in the shop loops and system in case we'd have issues with enough heat, which I'm glad we did this year.
With this system in order to feed the house first and foremost, we just lowered the temp in the water heater and cooled that system down some, to allow more heat to go to the house and keep that warm, works like I wanted, at least the house isn't cold, but we are robbing from the shop to feed the house, a double whammy when it comes to a warm spell, then my floors are cold and it takes all the heat the furnace will produce to get things back up and warm, and this winter, we never have enough warm days to allow that to happen.
The downside to an undersized furnace is it never catches up, and never gets up to operating temps, compounding the problem even more, as they say, a bad situation worse, by not getting things up to operating temps we're having issues with creosote buildup and I'm sure a lot more things I'd never thought of but I'm sure someone will point out.
As for the amount of wood, I don't think anyone could imagine how much we're pushing through the system, and I'm not sure I want to dwell on that for the moment either, it would be very depressing to say the least, but far cheaper than buying lp gas is my only positive thought on the subject.
As they say I know we have problems, when bad situations come along, problems compound as they are in my situation, with low boiler temps, come lower temps to keep the in floor heat hot, and as the floor cools off, the more temperature the floor requires to heat drawing off far more heat difference between the incoming lines and out going lines on each manifold, making things far worse than I'd imagined or could have, if the floors are good operating temps, there is about 10-15 degrees between the two, when the floors cool off, that increases even more to up to and over 30 degree's, so when my water heater temp is backed off from 120 to 80 or less, the lines coming out of the returns are far below 60 and before long, the water in the water heater is at 60 and things stall out very fast if that makes sense to anyone.
If this had been a mild winter, things would keep up and do fine, my current furnace is supposed to be near 500,000 btu's output but is non pressurized, others make a similar in size furnace that's pressurized and they claim it would play with my system even in adverse cold spells, so the big question is, would you gamble on a 15k furnace to find out just how accurate they might be?, or even higher priced to get another just like mine by the time all the prices are figured into the equation and keep two running?
The next issue we're having is something I'd addressed before on the forum, in floor heat having not enough surface are to shown to heat the building its in, or insulating the heat source from the heated area, right now we've had the shop full of equipment taking up far too much room in the shop and covering the floor space far too much, it won't allow the heat to rise and warm the shop. My plan to combat this was to eventually put forced air heaters hooked to the hot water too, to warm it up quicker when we're in there, but right now I don't have enough water temps to do much good.
As for air leaks and a draft, its an old barn, we insulated it the best we could but its not new or draft free by any means, I won't every claim it were, we tinned the inside with old used tin, and there are holes in the tin from before, so there's no real way to make it air tight in stiff winds, if it were new tin, it probably wouldn't have been so bad, this I never took into account when we used it, in fact it never crossed my mind it would be an issue, add in some area's that are concrete connected to cement block and also tinned and we have some air movement, not much but some, nothing like the curtains in the house blowing in the breeze but enough to add up over time on a large cavity called a shop. Nobody I talk to with furnaces have any real idea how take this into account, which was my original question of using square footage or cubic footage for figuring heating needs in the first place, its not new construction by any means and how does this increase heating needs for a boiler anyone want to venture a guess? Sorry this is so long winded but to get all the variables taken into account I didn't want to leave things out.
DING DING DING
I see a potential issue, if drop across loops is greater than 30 degrees and water is exiting floor at or near room temps you may need to increase pump speed.
Also, what kind mix (anti-freeze to water are you running) are you running? Anti-freeze can GREATLY affect pump speed/GPM cause its hardder to pump.
What kind of water temps are you see out at the OWB?
Also I know its been said 100x maybe more, but are you burning decent wood?
In regards to wood comsumption (7000sf - has comsumed 16 cords and counting); luckily know a logger who likes to drop of wood by the semi load for $$ of gas and maybe a beer or six
I used one of those infare red guns?? The ones that you point at a door to see the heat loss. That will tell you a lot too.
I heat my hot water with my OWB. I have a 54 inch one. I burn a lot of branches when I heat my hot water. May have to so called fill it,2-3 times a day,but I don't use much "wood".
QuoteCOMPLETELY DISAGREE, water going into a slab should never exceed 150f
littlejohn
I've had hot water at boiler temps running through concrete for just over 45 years and have seen no deterioration in the concrete. Temps set at 180°
So am curious where you are getting the 150° max info.
Does it have to do with expansion/contraction of the concrete or something else?
I suspect the water may be 180° but the concrete doesn't reach near that temp.
concrete can easily handle 180 deg. the myth and sales pitch is run cooler water temp and run you lines a foot apart, hum that comes from the guys selling the tubing. if you run hotter water and have a tubing spacing at 2 feet you'll have real good results.
my 20 yrs and beenthere's 45 yrs running 180 deg water with zero problems should put to rest any negative thoughts. :)
I know we have less heat transfer from anti- freeze mix but I didn't want it freezing this winter either, its mixed how the boiler people recommended for me, as for the pumps, those are grundfos pumps that are three speed and we run them on high, my plumber told me we could do the whole main shop on one pump it had enough capacity, but we run two for the main shop and another for the office. When we got things up and going this past fall, we had it ideal for incoming temps, outgoing temps, the floor was right at 78 degrees and the shop was toasty warm, there was about 15 degrees difference between the two, and was told it was great, but as it got colder, really colder, like in the below 25 temps and more, the water temps at the furnace are harder and harder to keep up, and when the temps at the circulation water heater dropped below about 100 things went down hill fast, the lower the temps at the water heater, the larger difference between the ingoing temps in the floor and outgoing, today we have the temps at the water heater about 70 degrees and the floor temps are right at 55 and the shop is right at upper forty's at head high levels, my furnace blower hasn't shut off in weeks and today the air temps are back up warm, and the wind picked back up to over 40 mph and its like trying to start the shop heat up from scratch, the entire cement is cold and not warming much at all and won't till the boiler temps come back up. Two days ago we had wind chills over 40 below and things haven't caught back up again yet, but I'm hoping this weekend sometime they will and my shop floor is back warm again. Another bottleneck is the plate heat exchanger in the office for the water heater, it will only transfer heat so fast, I was told it was plenty big enough, but I don't know for sure now if it is, it seems to transfer about 20 degrees off the furnace side to the water heater side, not sure if that's enough or not but its what we have to work with. When we robbed the heat from the shop to feed the house, we just switched the pump speed from high to medium and that slowed the heat transfer to the shop water heater and cooled off the shop.
I crawled up and looked down the chimney again today, tomorrow we're going to clean it out again, I'm starting to get concerned we'll have to cool the whole furnace down and get inside to clean everything out the way its looking, we usually just do it when we service it for the year but due to the really cold temps and not being able to get it hot enough long enough, we're getting far too much buildup and its affecting the draft of the furnace now.
As for the wood, yes I'm aware of that, I don't know if I mentioned it, but we ran out about a month ago, and have been cutting anything we can find, and mixing them as we go, its the best we can do for now, again compounding the problem, had it not been for the absolute bitter cold this winter, we had figured we had enough to last till early summer when we shut down, as they say its gone downhill from there, we had logs piled up in the timber to bring home this summer, but those I can't get to at all. So we're using what we can get to, both dead and alive and mixing them as we go.
Radiant heating schools teach you to not exceed certain temperatures because it can create problems. Things COOK. Beenthere and Redoaks your systems have been running at those temps for a long time and you are satisfied with them. I could not run a system at those temps for fear of tile breaking, cement failure, burning feet, and the huge amount of expansion and contraction it creates. I have seen cooked floors and they are a lot of work to fix, nothing like walking across a tile floor and hearing the sound of broken glass under your feet on every step.
Randy I have done heat losses on your building from your description and come up with 210,000 btus, but. If you have any cracks and openings to the outside that # is not valid. A 30' door sitting above the floor by 1/8" is almost a 4" hole to the outside. My version was for an 80 degree differential. An infrared temperature ,thermometer may well be worth investing in, and they are fun to investigate with. 8)
Randy 88
You have an insulation problem. The cold and the wind are wicking away your heat.
Rent, beg,or borrow but get your hands on an infra red camera similar to the one Holmes uses on (Holmes on Homes). It will show you where the heat is "leaking" out.
You can buy a lot of insulation for the price of a larger stove.
Hope this helps
Al
If you have equipment that needs oil changes (grease pit) you could supplement your shop heat with a used oil burner. Plug any air leaks you find . This has to be done or you will never keep up with the wood burner.
I never put 1/2 inch pex farther apart than 6"on center . Pex is one of the cheaper parts of the heating system. If you have heat tubes more than a 8" apart you will have heat striping in your floor . [ hot over the tube cool in between.]
I'll try to locate a infra red heat gun, anyone know where to buy one and what they cost? We can try that but I'm not sure we're going to ever get it as air tight as house or wood working shop, just by what we are working with and its basic design and nature of it being used as a shop.
So in order to deal with what I have, a large equipment working shop, what can I do to help the situation out beside looking for air and heat loss, would it do any good to add water storage to the existing system for heat reserves to be built up for the cold spells and hopefully when it warms back up [like we usually get most winters] it can catch back up again and replenish the system.
Would it be economical as far as wood burned to buy an industrial outdoor boiler to replace my existing owb but a lot larger both in water storage capability and also btu's or will that just burn excess wood in the warmer milder weather in the fall and spring, would it be any different than two or three smaller units or do you gain in efficiency when I'd go larger in one unit, any thoughts or ideas on that question?
I know I have a lot of concrete to warm up, if I recall right its in the neighborhood of 150 yards, my lines were between 6-10 inches apart depending on where the lines ran and how it came out for the footage on each line and also what part of the shop we wanted warmer.
I'm not thinking we're ever going to get anything down to the efficiency factors to do the heating in x number of btu's like the charts claim.
I know when we priced to have lp gas convection heaters hung on the ceiling they used cubic foot calculations to do the math, and were putting in a lot more total btu's of heating in the shop only than any of the outdoor wood boiler people recommended, they told me when I asked, your not dealing with a house, its a shop and the doors opening and closing and size of the room required far more heat and that's all I got for an answer, then they wanted to install a lp boiler to run the in floor heat on top of that.
I understand that my heating needs are much higher than most, I'm also prepared to handle the wood and fill the furnace to match my heating needs I knew this when we set it up, my only concern is not going overkill, and not under sizing the system either.
Anyone have now, in the past or know of anyone with experience dealing with large industrial sized outdoor boilers, I know a few company's make up to 3 million btu outdoor boilers, that million btu that I had calculated isn't out of the question, or I could go with another similar sized outdoor wood boiler to add to my existing system.
Anyone know anything about wood chips and outdoor wood chip boilers, I've considered in the past going with an average sized wood chip boiler and hooking it up along with my firewood boiler for the extreme cold temps, anyone with experience with those units, good, bad??
randy
i added up my sq.footage at the shop, my footage is alittle more than what your doing. i looked at the type of stove you have ,best i can tell mine is about the same size. all my heaters are modine style(forced air) my big door is 18x11 which is opened several times each day.running a large dust collection which sucks alot of warm air out. my kiln which runs 130 deg.(1050 sf) is also supplied by the one stove. even with all the extreme cold this winter my stove runs less than half the time.
is your stove being fired the proper way? i'm not asking what your fueling it with but, there are right and wrong ways of feeding the stove. don't take it personal i'm just wondering.
your stove isnt a gasser is it?
Real good thread here.
Randy, would you mind supplying us with the actual temps of the water entering and leaving the radiant system instead of just stating the temperature drop (15 degrees)? thanks.
What are the temp settings on your OWB and how close does the effluent water temp get to that top setting?
From what I have experienced all factors have to be included for a proper estimate of required BTUs, the calculators that I have found on the web are mostly rough estimates and rule of thumb compared to getting a real quote.
I priced out a few heating system for a buildings over the years, I do remember being asked for things like insulation value, kind of windows, area of windows and doors, ceiling height, weather stripping, shading and exposure to wind. there may have been more that I forgot.
My experience with in floor heating is limited to my house but have much the same problem except on a much smaller scale, my living room is about 1/4 of the sq footage of my house but I send most of my heat to it. The ceilings in most of the house are 8' but the living room has a cathedral ceiling and much more glass area.
I don't use zone valves but instead I balance out the system with the ball valves on the manifold, with the living room getting most of the heat and it still takes way longer to get it up to temperature than the rest of the house, I'm pretty sure the living room is getting more than enough BTUs if the heat was delivered a different way but the floor can not radiate the heat to the room fast enough to fill the demand, I get by but one of these days I would like to add some rads to the living room to deliver the heat faster.
If you do find that you need more output I wonder if it would make sense to split the system and use the current OWB for the shop and get a smaller one (cost less) to do the house, If the house was taken off line for a few days you could see if the OWB would be large enough for the shop.
Before we say you need a new boiler . You said this system worked ok last year as it was milder. Half a million btus should heat your buildings. Can you get your boiler up to maximum performance? Will that require,and can it be done with good dry wood? You need to get the boiler running properly first.
The heat exchanger for the water heater that feeds the garage radiant, is it rated for 2 to 3 hundred thousands btus per hour with circulators moving water thru each side?
What temp are you trying to run in the garage slab?
Infrared thermometers are $50 and up.
Last year we didn't have the entire shop up and going just the office, all the rest of the large portion of the shop was unheated since I didn't have the door on, we worked on that all winter long in the cold. So all we had was the house and office on the furnace, its been like that for a couple years now at least, this fall we got the manifolds on and the lines hooked up, pumps put in and got the hot water heater to use as a collection point for the entire shop to isolate the shop from the furnace.
Our owb is set to kick off at 180 and come on I think at 150 but that thermostat is so smoked up I can't read it anymore. In descent weather, not this -30-50 below stuff for weeks on end, but more normal weather, things work just fine, we can keep the temps at the furnace up, and it cycles on and off like it should.
The water going from the furnace to shop is in that cycle range depending on if the blower is going or has just shut off. Like it should be.
The water heater has a pump hooked up the heat exchanger and we hooked up the thermostat on the water heater to cycle that on and off, we have the temp in the water heater set at 120 or so, when the temp in the water heater gets up to 120 the circulation pump shuts off and no water is run through the heat exchanger to feed the water heater. This too worked fine once the concrete floor was up to operating temps in the in floor heat.
The house has another line and pump feed off the back of the furnace to feed the house, it goes into the sidearm to the water heater in the house, and then through the radiator we have above the old gas furnace, which hasn't run in almost five years, we just use the fan, that's almost 30 years old and my fix it guy said to not worry about spending money on it, just to use the fan till it dies, then we'd figure out plan B, which as of yet we haven't had to worry about. Then the water goes back out to the furnace. Again this works just like it has for almost five years now, when its mild, things work great, plenty of hot water, more than enough heat to heat the house.
Back to the shop, with 120 degree water coming out of the water heater to the pumps, we don't have much temp drop to the first few manifolds, but not all my manifolds are together near the pumps, in order to isolate leaks in the future, we ran pvc lines under the concrete to the different zones, so we ran the pex inside those pvc to the remaining manifolds, on those three manifolds we did that with, there is a slight temp drop, maybe 5 degrees when it gets to those manifolds, nothing major and on all the lines, we have return temps out of the lines about 15 degrees less than the 120 or 115 degree temps and then it goes back to the water heater to be reheated.
Now we've had months of below zero weather, something like 67 straight days of temps that never got above 32 and 30 some straight days the temps in the morning were never above zero, on the warmer of those days, we've had so much wind, the wind chills have not gotten above zero in over two straight months, I've kept track and so has the local weather man on tv I listen to, we have that love hate relationship going on, I love to hate him when he gives the depressing forecast for the day.
In very mild weather, we don't have an issue with the temps at the owb, but when the wind kicks in, or the temps stay down in the below zero temps for weeks on end, its a slowly losing battle, first the furnace cycles longer, before shutting off and before long, it never shuts off, my boiler temps start to decline gradually over a period of days, this last couple of weeks, we've had a hard time to keep the boiler temps above or even at 150, then they creep down even lower to 120 and never gain back up, that's about when we slow the water transfer down in the shop via slowing the speed of the pump on the water heater down, slowing down the heat transfer in the shop and thus lowering the temps in the water heater, that in turns starts to decline slowly over days and weeks, once the water temps in the water heater gets down under100 it drops pretty rapidly down to 80 and a few days ago it was down to 60 and the temp at the manifolds equaled out at 55-60 on both side, into the cement and back out of the cement and the shop was down near 40 degrees for days. A few days back after months of below zero weather when I started this tread, my boiler temps we not ever over 100 degrees, no matter how much wood we shoved into the furnace, how often we were firing it, we just shoveled in wood and watches the temps hoover, basically my thoughts were we were under the user curve, it sucked more out of the system than the system could generate, or from a system too small to handle the load.
Once the weather warmed up outside, we've been working our way back up in temps again, yesterday was the first day in weeks we got the boiler temps back up to 180 and it cycled off and the fan quit, then we turned the pump speed back up in the shop and have been warming that system back up again. My transfer rate on the heat exchanger isn't quite enough is my thoughts because we as of tonight still don't have 120 degrees back in the water heater that feeds the shop, maybe 100 or so, but the temps going into the cement and back out on each manifold are now spreading, maybe 95 ish going in and 75 or less coming out of the cement. Now the lines closer to the large door is still a lot colder, since its the wall that has the least amount of insulation in it, only the 4 inches in the door, also the coldest area of the building, so to me that makes sense it'll take the longest to warm back up again.
If the temps outside are near zero or above, we don't have issues, but when the wind chill picks back up and punches the wind chill temps in that severe cold for extended times, I'm in trouble, if the temps only dip lower for a short time, we don't have issues.
This furnace isn't a gasser furnace, just a simple firewood furnace, non pressurized.
Now for the sales pitch end of the explanation of things, I'm told since its not a pressurized boiler, the company doesn't have to offer scientific data to prove it has x number of btu's of output, and my plumbers are telling me, I don't have a large enough furnace to do the job, since they don't believe it is indeed as big as its supposed to be, reality or just myth, do I actually have a 200,000, 250-300,000 btu furnace, is the major question we're dealing with. I'm told by certified pressurized boiler manufacturers, they have indeed a 500,000 btu furnace that will more than do the job, they also have a 300,000 btu furnace they claim will do the job just fine, and they they claim mine isn't anywhere near 300,000 btu's and I'm short from day one on size?? Good question, hard to prove till I spend dollars to do it, provided we have similar weather again, might never happen, I haven't seen a winter like this ever, we've had cold spells before, but nothing that lasted and lasted and the wind blew every day for months on end.
I have a Heatmor,400 DCSS. They claim it will heat 10,000 square feet,400,000 BTU. I have no idea if this is true or not. Almost like the hp a few years back on small motors or some claim the tonnage of a wood splitter. My fire box is 54 inches long,26 inches wide and with a built up of ashes,26 inches high. Hope that helps. I don't use the whole capacity of the OWB. I did want a working garage,but the way things are now,I don't see that happening.
Sounds like you understand your situation and know exactly what needs to be done. Is the garage your lively hood? Can you consider putting a wood boiler inside the garage? Put a small addition on the side of the garage to house the boiler?
Nothing like spending money twice and get things right the second time, but that weather was not predictable . Just think , walk out to the warm garage to feed the boiler , dry wood ready to keep everything warm and not being all bundled up fighting the sub zero weather.
Or leave the boiler as is and spray foam the garage. The foam would need to be fireproofed.
your set point on your stove should be alot closer.if your boiler shuts off at 180,it should kick on at 170 or 172. keeping your water mass closer to high the faster your recovery. why keep trying to reheat alot of water? is your water level ok on the stove?
on your induction fan does it have an air damper on the side of the fan or is it wide open to draw alot of air?is your fan in the door? or the front of the stove ?if so, do you rake the coals to the front edge of the stove and stack your wood just inside the door to allow for max burn.
i know others dont believe your in floor water temp should be very high but, 120 water in the floor will keep giving you poor results, crank it up to atleast 150 deg.
when we built my son's house in 2008 we had infloor heat put in. the heating guy insisted the temp be set around 120 so, a disscusion insued and i called a large concrete outfit in the twincities and spoke with the engineer about water temp in concrete. his answer was there wont be any failer until atleast 250 deg. so with that we set my sons temp at 170 going in the floor, which parts also have tile on the crete.
Around here nobody has ever recommended anything for temps going into concrete anything over 120, if others are doing it higher with no adverse side affects, I'll gladly up the temps, that's an easy fix, but while on the discussion, how hot can the concrete get on the surface before there's an issue? The reason I ask is this, when we're opening the door in frigid temps and let the cool air in, everything will kick on to high to regain what was lost, with water temps going into the concrete at 120, about the highest we ever got for a floor temp was 80 or slightly over, with the water temp set at 150 or more will the floor temp on the surface get over 100 when it calls for heat or even more, like 110-120 before the heat in the building is built back up, or how does it work? Sorry its a stupid question but I gotta ask it anyhow.
Next thing is the temp differential on the furnace, its how it came from new, I've never messed with it, but I can certainly reset it to come on a whole lot hotter, to me that makes simple sense to not let the temp spread get so much, every time I've asked, I've been told to leave it alone, we'll do that this morning right away, clean up the dial so I can read it and change it.
Next question I have, does or has anyone taken exhaust temps on their furnace before to find out how efficient it is in all reality? The reason I ask is this, I've been told that the cooler that temp is the more efficient the furnace is working, so the hotter the exhaust is, the less efficient it is, I guess this makes sense to me, you'd want to retain as much heat into the water as possible and cool the exhaust as much as possible, but my question is, what should that temp be?
With weeks to months of so adverse cold conditions and my furnace not keeping up and really getting up to temps, I'm pretty sure we have excess buildup and we're now fighting the issues of less draft, not as efficient and much more heat going up the stack and not getting into the water at all and was curious what that temp should be coming out the exhaust close to the stove, we don't have a tall stack on the furnace, just what came with it, a couple feet. The downside of this is I can't get in and clean the creosote out till the furnace is shut down, cooled down and we have to get inside the stove and work to get it cleaned out, a very poor design to say the least, another reason why I'd like to change out the furnace and find something different.
As for putting anything into the shop, not going to happen, its too small now, we need to add onto it and was planning on doing so in the near future, but with how it lays in the yard and its design, we can only add on about so much, which we plan on doing just to hold all our stuff we need in it and to use it, yes its my living you could say, everything evolves around the shop.
As for the furnace, we have a fan in the door and we pull the coals and unburned wood towards the front each time and fill it till we can't cram any more into it. In adverse cold conditions, like we've had this winter we've been filling it no more than every six hours, more like four hour intervals, basically it can't burn it hot enough fast enough to keep up to load we have on it.
Next question I have is this, since the answer I get is to "not worry about it" but how much larger should the furnace be in order to factor in the extreme cold conditions, even if we never have another winter like this again, I'm pretty sure I've learned my lesson on marginal or "adequate" sizing of a furnace. I told the last one who told me not to worry about it, just go by the standard sizing and be done with it. I told him, why don't you figure out how to get more heat out of system that's not big enough when its 60 below for weeks on end and its cold everywhere but when your shoveling wood into the furnace. As they say I'd like to have a system large enough to play with everything factored in, not struggling with everything factored in. In extreme cold conditions, do you double the heat load, only go a 1/3 larger, 50 percent larger, what? Those average temps of rise needed get a whole lot more when we start to compare 10 below temps for a few days, to 50 below for weeks on end, not sure about anyone else, but when its frigid, is when I need the furnace the most and it needs to keep up, not struggle or wishing it were larger. I've asked this question to many I talk to and they'll gladly sell me a larger unit, the question then becomes, is it big enough for the extremes or far overkill, then it gets quiet on their end, basically they don't know is what I think. Don't worry the lp gas furnace experts don't know either, their solution was to put one convection heater in, if its not enough put another one in, if that doesn't do it, put in a third, whoa, that's telling me, they don't have a clue either. I guess I'm asking because there are a lot of owb's in that 300,000 btu's, a few in the 400's and some in the 500's and the next jump is up to the 600's, but most companies have a large jump in size from say 300 to 500 but not have another one till it gets to say 750,000. If one third is large enough, is one thing, but if I need double, then more than likely I have to find another company to buy one from company x doesn't offer one in that sizing type of deal.
The plumbers in my area are telling me to buy a pressurized unit, for two reason, help on the rust out issue's I've had on this one, and more importantly, those have to have proven data of btu output due to the regulations put on those furnaces that non pressurized systems don't have to go by, so my question is, is this indeed true, so if I'd buy a pressurized outdoor boiler, and they list the btu output at 500,000 that is indeed what it puts out and I can take that guess work and overblown hype out of the equation.
As they say, there's always a bright side to every dark cloud, so if someone who reads this can avoid my type of problems, at least someone will gain from my experience, not sure how that will help me other than to say, been there done that when I'm 80 and remembering the "good old days" and that miserable winter of 2013/14 when I almost froze to death, you know by then I'll tell everyone, we had to heat pots of water on the stove to wash our hands and it was up hill both ways to fill the furnace,, and we had a chair there so save the commute to and from the furnace, gosh I can just hear the stories my grandkids will hear when I'm older and greyer than I am now.
Red Oaks is right on with the differential setting, move it to 172. Hydronic heating systems are usually designed on 180 degree water 180* will get you 550 btu's per foot on baseboard radiation 140* will get you 300 btu's per foot. The drop off is dramatic as the temp goes down.
Running the water temp in the floor at 130 to 150* is up to you. I will not tell you it is wrong just not recommended ,others do it and it works for them. Ramping your slab temp up a few days before the cold spell is supposed to start may be a big asset for you and that would require 140* plus water going thru the radiant tubes. it may be the only way. An infrared thermometer will help you figure out if all of your loops are warming up and if all of the slab is warming up. Its a standard tool for researching heating problems
Boilers are sized by total btu output 100000 btu 80% eff. should give you in your building 80,000 btus. Your wood boiler may be rated at 450,000 btus but you may be lucky to get 55% eff from it not to mention it looses heat to the outside. 450,000 x .55= 247,000 btu's.
What do you have to do to Not Worry About It? ::) :P Bigger and better ? That is a good question . :)
Snap On tools has a very good temp gun. Don't know what they cost as the one my son has was part of a racing sponsorship. splitwood_smiley
Quote from: Randy88 on February 13, 2014, 10:02:06 AM
Heat lines are half inch, each run is 300 feet or less, some had to be roughly 265 to come out,
Are you sure the main lines are large enough. It appears to be an awfully long ran for 1/2" lines.
Also with the lines this long, how much energy are you losing into the ground. Did you super insulate the lines or are they running through frozen ground? I wonder what the temperatures are leaving the boiler and what they are when they enter the building(s)?
Bruce
Reading the last few post has jogged my memory some.
Thoughts,
If you don't find any thing wrong with the way the your current OWB is working and it really is undersized for the task and you put in a higher capacity one with the same efficiency rating I would think that you will be burning even more wood to get the required output.
Things that I have done to combat falling behind on my heat are:
Increased the temperature of the water going in the floor from 120° to 135°.
Increased the temperature of the boiler for the really cold days, spring and fall = 170°, normal winter= 180°, very cold winter days 195°
Increase the on and off settings on the circulator when increasing the boiler temperature.
And the one that makes the biggest difference once everything is working right is to keep an eye on the weather and dump LOTS and LOTS of heat in the floor before it gets cold.
Sometimes I get the last one wrong and get too much heat in the floor or not enough it takes practice and I have to factor in things like current indoor and outdoor temp, if the sun is shining, the wind strength and direction, where I am on the heating curve (speaking about in floor heat) example: 72° on way up (just put lots of heat in the floor) versus 72° on the way down ( sunny day and the heat has not come on for 8 hours) are two totally different situations. Think of it like driving a loaded tractor trailer and getting a run on before getting to the hill works better than waiting until your there, less down shifting required. If i mess up (miss a shift) and don't get enough heat in the floor before it gets cold I get out the portable electric heater and plug it in.
submarinesailor, my main lines to and from the boiler itself, feeding the buildings, are one inch, the one's in the concrete or runs are 1/2 I'm thinking right off the top of my head, there is 2 inch foam board under the concrete, and along the walls on the inside of the building, x feet deep, all around the outside of the service pit, and also the footings for the service pit.
The one inch lines to and from the buildings and boiler are those inch lines in the four inch tile foamed in place, bought in bulk footage and six feet deep, I dug that in myself and wanted it far enough below frost level to not have heat loss from frozen ground, the only place it could be in frozen ground is where it comes to the surface beside the furnace and feeds into the back, my furnace is set on an elevated concrete slab, almost 1.5 feet elevated so I didn't have to bend over to put wood in the furnace.
While on the subject of concrete, seeing how I'm dealing with far more than most, in terms of thickness, and I've never gotten an answer from anyone on this, does it require more btu's to heat concrete 8 inches thick or more, verses some that's only four inches thick. My plumbers didn't know, but an educated guess was, "shouldn't" once its up to temp, and then my very next question was, how about getting it up to temp, followed by total silence.................... I've never bought into the idea of taking no more btu's to heat 8 inches thick concrete, verses 4 inches thick, maybe I'm wrong, but its still mass to heat, less mass less heat required, and far less to maintain, once hot the mass should stay hotter longer, but I don't know how that translates into btu's needed to do both.
The infra red heat gun, are you guys calling those the one's that show the screen of different colors for different temps of heat loss or the laser pointer temp guns you aim, shoot and get a digital readout of that exact spot the laser points to?
Randy88
I think the proper term would be a Thermal Imaging Camera.
They are expensive (the ones we bought last to year use in the Forrest Fire program) ran about $7500 Can.
It would be foolish to buy one check your local "yellow pages" and find an individual or company that does that type of work.
Contract with them and have them come out and do your place (shop , house , stove the whole shebang). I can guarantee that you are going to be surprised as to where your heat is escaping.
If you insulate with foam you will have to cover it the code up here calls for drywall and the thickness is governed by the local fire codes (industrial, commercial, residential).
Where I live I am no stranger to cold and wind, the colder it gets and or the stronger the wind puts a real load on any heating system just by building a enclosed shelter for my OWB made a difference in wood consumption (keeps it out of the wind and snow).
I have heated with an OWB for 22 yrs. and Have learned a few lessons most the hard way.
For what they are worth here are several of them.
1/ I have my aqua stat set 185 to 195 (as my stove came set 165 180, one notices the difference in heat transfer once you start dealing with steady -20 f temps)
2/ Resist the temptation to stuff the stove full. Your burning cycle is governed by the water temp and wood being a near perfect insulator will shield the heat exchange surfaces and a lot of heat will go up the chimney until enough surface area is exposed.
As an experiment try reducing from stuffing it full to say3/4 full, I personally try to keep mine no more than between 1/2 and2/3 full . With that being said keep the ash level down my stove requires me to manually shovel it out.
3/ Try to burn dry wood as green wood takes energy to drive off the moisture and that lost energy is not contributing to the heating of the water. There are two camps on whether to use round wood or split wood I split my wood so that it can dry. I use a lot of Paper Birch and it will quickly rot in round form (the bark being impervious to water they made canoes out of the stuff!)
Hope this helps
From the land of ten months of winter and two of poor sledding
Al
Infrared thermometer with laser pointer. The thicker concrete gives you more stored energy. You are not loosing heat just storing more of it. the difference may be noticed when you get a warm day and the garage ends up being 85 degrees, no heat loss to the outside so the inside gets real warm.
Is there a way to calculate the circulation time for your radiant loops? It seems to me that your stove temp definitely needs to go higher, your lower end of your water temp bracket is too low because you need to deliver warmer water to the flooring. I run my OWB at 185-195 always. I have a 300' run to the house, but my pex is 1 1/4'. So, while increasing the temp of the water in the floor will certainly deliver more heat, the length of the circulation loop may be too long and will outstrip any adjustment you make, given your outside environment. If the water is "exposed" to the cool concrete slab for too long a period (too long a loop / too slow transit time), then the amount of heat loss may not be able to be overcome by your OWB. So, I agree with the suggestions of Hilltop above. Ramp it up and see if it can keep up.
Holmes, where did you come up with the efficiency factor of 55% for owb's, does that include all owb's or just an average, or are they posted somewhere for most all owb's on a per model basis?
I'd like to say thank you to everyone who's put input into my problems here, I have learned a lot.
I guesstamated ;D Wood stoves run about 70% without a catalytic combuster , Wood boilers run 75 to 80% with gassification . A while back there were discussions about the efficiency of OWB as gassers and non gassers . I believe the numbers stated then was 60 to65% for non gassers running properly. Yours is not. Lets ask doctorb,{passing the buck ;D} I believe he found a couple of sites that stated % eff. maybe EPA numbers.
Holmes, sorry to pester you on this issue, but in order to achieve my needed 300,000 btu's of heat for my current needs, and lets just say to be on the safe side in all reality I'm actually getting around that 55% efficiency, maybe higher at 60% on milder days, how much more would it require on adverse days than the 300,000 btu's of heat to heat the buildings, any idea?
Everyone I talk to discusses average temps for my area, I get that and their reasons for doing so, but maybe I'm wrong on this, but in average temps my system does fine, its the adverse temps are where I'm in trouble, at least that's where it seems to me I'm having issues, now not to beat a dead horse, but as beenthere stated in the beginning of this thread, maybe I need my furnace and add another on, or go with a larger one altogether, which I can't argue either way as of now, I'm pretty sure my system is too small with adverse weather. How do I go about figuring for adverse weather like we've been having? If I were to add another furnace on, how big should I size it or how do I even go about figuring it, tell the sales people I live in northern Canada or in the arctic or I want to calculate in a minimum of a 100-120 degree's heat rise on my system or how?
The reason I'm asking is this, a company is telling me their 500,000 btu stove is so overkill they heat a 30,000 square foot manufacturing facility with that furnace is too large even for them, so I went to look over their facility, which is first off, in town, that's in a valley, that's surrounded by tree's, there are no windows at all in it, its all tin construction, and the boiler is out back behind the facility and in a wood shed. It could be blowing 100 mph winds and that facility would never even have the leaves on the tree's rustle in the wind where its located, the ceilings are maybe 10 feet tall and they spray foamed the ceiling and walls with two feet of insulation. My buildings sit on a ridge, in the open, nothing around them but wide open space on all four sides and when its somewhat windy out, say 30mph its white out conditions in my yard and we can't even see the outbuildings, my house has 6 inches of insulation in the walls and on those days with 50 plus sustained winds for days on end, my whole house creaked and groaned from the wind gusts, my shop was about the same and that had 10 inches of insulation in the walls and a foot or more in the ceiling. I'm not thinking some of these companies grasp the full understanding on wind chills, let alone not everyone has feet thick of spray foam in their walls or ceilings, as they say location has a lot to do with conditions. How do I equate that into a formula I can use, stating I need x number of btu's in my buildings after all the factors are figured in?
The adverse conditions will change the infiltration numbers, [air changes per hour], ach. Your 32'x80'x 20' shop size times 80 degree{ temp differential} x.018 =73728 btu's per hour with 1 ach. You are probably getting 2 to 3 ach in the cold adverse conditions with each ach adding about 75,000 btu's. I would say you should treat your shop like an uninsulated building for boiler sizing. That should get you in a warm building.
If it is getting milder and you can ramp your floor temp up to say 86 degrees it may give you a better understanding of what needs to be done to stay warm.
Are you looking at Wood Doctor boilers ? I looked at their site seems like a good product and they appear to know what to do about sizing.
OOPS >:( just read your review on wood doctor. :o
I'm hoping the worst of the winter is over, or at least the extreme extended cold spells anyhow, and I have time to formulate a plan for next year, ask more stupid questions than I already have, listen to more sales hype and try to weed out fact from fiction and now have a slightly better idea of what I should be looking for and at.
Thanks for the information and opinions given thus far.
If you get an infrared thermometer you will get a lot of use out of it. Start now and go all the way across you garage floor and check temperatures. You may find a few loops that are not circulating. You may also find some cold areas when you point it at walls, doors, and everything else Write the temps down for future reference. On a cold day check you concrete temp. when you feel comfortable in the garage. You will get the hang of it when you get 1.
Got the laser thermometer and did some checking today, first off does anyone know how much more heat from the outside sun a cement block or concrete will absorb verses wood or tin? The reason I ask it was actually nice this afternoon so I went around and the tin surfaces on the shop where there was 10 inches of either blown in or bat fiberglass on the inside of the shop had outside temps of 38 degree's, no matter where I shot the temp off of, the cement block were somewhat higher temps, but all the same as well, those were 40-42 degrees depending on which side of the shop they were taken from, and the very same for any concrete surface. After dark I went back and shot all the same surfaces again, the temps dropped which I expected, tin was 33 degree's, cement block and concrete were 35 degree's. On the inside of the shop the tin surfaces were upper 40's towards the mid way height of the wall and towards the floor they were near 50.
The shop floor today was in the mid to upper fifty's about anywhere I shot them, my water heater still hasn't caught back up yet from the sub zero temps we had last week and those temps were still under 80 and warming yet. In the office, the floor was mid sixty's, but that area has only 8 foot ceiling and just that area is on one pump, it should be warmer, we set it up that way, those inner walls were lower 60's about anywhere we shot them.
Anyone know if this sounds right for the difference in temps from tin to concrete or cement block, I plan on shooting the temps again in the morning both on the inside of the shop and outside, I expect the outside temps after the whole night to be closer to the same on tin verses cement block.
On my furnace, the only place there was a difference was where the chimney came through the roof, there it melted the snow away, otherwise the snow was still on the roof and the sides were the same temp, the water lines coming out the back had snow on them all day long, can't imagine there's much heat loss there and I never shot them for temps.
I never gave it a thought today to shoot the outside of the house on the vinyl or cement basement, guess it never dawned on me to do it.
On the shop door which is the least insulated of anything on the shop and tin on the outside, that temp was 40 anywhere I shot it, the double pained windows I put in, which are a foot by two foot rectangle basement windows, were also 40 degrees on the outside, never shot any temps off it on inside, we got busy moving snow by then and spent all afternoon and till after dark to do that.
I pulled some tin away on the inside of the shop by the floor, my in floor heat is inside the floor but not under the insulation, so I shot the cement on the floor under the insulation and also beside it on the heated portion of the floor, the unheated portion under the insulation was lower forty's, and the heated floor beside it was mid 50's, so my thoughts on this was heat wasn't really escaping out the walls through the unheated cement. The cement block on the inside of the wall, behind the insulation was a few degree's warmer than the outside temps, about 43 degree's during the day, we put the insulation and plywood back so we couldn't do it again at night.
Anyone want to venture a guess if this sounds right or not or am I losing far too much heat out the walls or where?
I also never had time to climb up into the attic to shoot temps up there, basically I forgot about it, and didn't get a ladder to shoot temps on the ceiling in the main shop, that's 20 feet up or the walls towards the ceiling either.
You will lose temp thru the radiant slab to the outside unless you super insulated it. The snow melts around the foundation of the old farm house and those walls are spray foam insulated. Try getting your slab water temp up to 130 - 140 . If you have even heating across the floor ,all of the loops are working. Ceiling temp should be about the same as the shop temp. Radiant works from the floor up conventional heat works from the ceiling down. With radiant you do not want the ceiling to be warm. I will looks this over after work.
When you move equipment into the shop it is the same temp as the outdoor temp. so if you bring in a in 10 ton piece of equipment and it is 10* outside it is 22* colder than a 10 ton block of ice. It will take awhile to warm it up. splitwood_smiley
Some updates I've encountered, there is no thawing anywhere around the shop at all, we've banked up snow on all the sides we can to help insulate it, which I personally don't think is the problem. We've taken some advice from here and unhooked the pumps, found some really dry oak firewood to burn in the furnace and got the water temps up to temp and the fan shut off, which is fine and how it should work, but during this experiment we cooled off the house and shop more than it already was, it wasn't a windy or subzero day at all, just colder than normal and we kicked the pumps back in again, the second the fan kicked on it was a pretty steady downhill slope with the water temps in the boiler, in fact the fan hasn't shut off since and that was over a week ago, now we're back to square one again. We added some supplemental heat in the shop on cold days, from my old diesel salamander heater to get it up to a working temp of between 40-55 degrees and that helped a lot.
My next idea was how much heat and btu's does it actually take to heat the hot water in the house, does anyone know an answer to this question?? Then we compared my summer wood burn for only the hot water in the house compared to what we burn to heat the house and water in the winter, shop left out of the equation completely and we figured we use from 1/3 to almost 1/2 of the wood it takes in the winter, so now we're going to change the plumbing in the house to bypass the water heater and just heat the house, see if that helps any, but I haven't had time yet to do this.
Then we went shopping and asking questions locally, talked to outdoor wood boiler people, whom I don't know personally, then onto plumbers I do know, they told me nobody's having good results this winter with anything, either wood furnaces in the house, or outdoor wood furnaces, none are keeping up and are all undersized. One I know told me to toss out the btu calculations and forget about them, this winter none are accurate and doing the job, everyone's heating system is taxed to the max, and most are not keeping up at all, some newer houses are even freezing up due to the small furnaces installed in them so they were energy efficient. We checked into waste oil burners for the shop to supplement heating that, the guy who sells and works on them is a friend of mine, who also has infloor heat in his shop, which is not doing any better than mine, he was having the same problem with his waste oil boiler as I am with my wood fired one, runs all the time and its cold in his shop too, he told me nobody's in floor heat in anything is keeping up this winter, he then gave me names of people in the area with infloor heat and having the same issues as me, some using natural gas boilers, some with waste oil and others with wood fired, all having the same problems. The only thing that did for me was knowing I'm not the only one. A third plumber told me to double or triple the btu calculation and if its infloor heat it won't be enough, for some reason this winter with the extreme extended cold in floor heat isn't the answer, some are even hooking up convection heaters or forced air heaters in their shop to keep them warm on top of the in floor heat.
Three plumbers and one waste oil burner sales people all told me the same thing, this winter is unprecedented and nobody's sure what to use for a formula for calculating btu's for heating needs in a winter like this, I asked them all what to do and none had a real answer. Anywhere from doing nothing and waiting till next winter, to doubling the btu's heating needs, tripling the btu's to adding more heating sources for next winter to use as a backup.
So where I go from here is yet undecided, but apparently I'm not alone with this same problem in my area, I don't think they'd all lie to me, none know I talked to any of the others, most don't even know each other so I thought I got an unbiased answer that was pretty much the same. After two of the guys tried to sell me their heating and plumbing business because they were bombarded with more questions this year than they can answer, more people ticked off at them because their furnaces won't keep up and their house or shop is cold and a dozen other things to toss into the equation, they were about fed up and wanting to quit. I assured them I wasn't mad at them, just wanted an opinion and also wanted to make sure they didn't quit, I do business with them all to some extent. The only outcome I got was I'm glad I'm not in the plumbing or heating business this winter in my area.
Misery loves company. Sounds like others are having the same problem. That is too bad.
randy
i'm not sure i would buy the answer, nobodys system is keeping up this year. we arent excatly located in the banana belt up here but, besides using more wood our systems are keeping up no problems. infloor or forced air. like i said before my shop space is about the same sq.f.t plus i'm heating my 15,000 b.f. kiln all with one stove.
its very possilbe your stove /design just isnt good enough for your application.
While it is true that this winter has been "WORSE THAN NORMAL", wood (aka fuel) consumption for residental heating has gone up this year.
According to weather man out of St. Paul/Minneapolis - 5th coldest winter all time; 50 days with below ZERO temperature.
Everyone is feeling the hurt this year
I haven't been around long enough to follow the entire thread, but I thought maybe you could use this link to some free heating and cooling design tools. In particular, follow their link to HEED. We used this tool to confirm the heating and cooling requirements for our home when it was being built. It turned out to be spot on, much to the chagrin of the HVAC guys who didn't believe it.
Although it is primarily aimed at houses, there should be no reason it won't work just as well for a shop building.
http://www.energy-design-tools.aud.ucla.edu/ (http://www.energy-design-tools.aud.ucla.edu/)
I was just thinking , But if you live in a rural area you might have a free fuel source laying in your road ditches , used tires . I usually get ten to twenty of them a year. One of them things will bring up the BTUs of a fire right quick. Might only need one or two a day to spike the water temp . ADM uses tires in the Decator Ill.plant . Might want to make sure your warrantee has run out on your furnace .
Quote from: Don_Papenburg on March 08, 2014, 10:13:36 AM
I was just thinking , But if you live in a rural area you might have a free fuel source laying in your road ditches , used tires . I usually get ten to twenty of them a year. One of them things will bring up the BTUs of a fire right quick. Might only need one or two a day to spike the water temp . ADM uses tires in the Decator Ill.plant . Might want to make sure your warrantee has run out on your furnace .
How does this go over with the EPA, or the state equivalent? Or don't they care in IL?
They grumble about everything . Tires are mostly petroleum . If you can clean burn them ,that is with other things, lots of wood for instance the smoke is only lightly darkened. If we pick up the tires the gov. wants us to pay to dispose of them . then they get sold to ADM or some other big industrial plant so that they can burn them. I guess I should have added ;) ;D