water temp

[coxy]

what would happen if I put my water temp up 205 would that mess any thing up

[Holmes]

If this is for an outside boiler you could over ride that temp and start boiling off your water. Other than that it will deliver more heat to your house.

[coxy]

sorry should have said owb you can turn my temp up and down thought that a little hotter water for hotter heat    doesn't water boil at 212  that's why I thought that I would be safe at 205   just thinking     that's why I am in hot water all the time for thinking :D

[homeyd]

i think you stand a chance of boiling.if so you could pullin a steam bubble and damage the pump or airlock the system

[beenthere]

cpxy  coxy  (sorry  )
Your system not keeping up now?

[coxy]

no its fine but the wife cant make me leave well enough alone she wants hotter heat  ??? I think its to darn hot in here now  don't know what she s thinking and some times don't want to know thanks for the in fo     ill let here read this my be she will find some other thing for me to mess up  :D

[coxy]

cpxy
Your system not keeping up now?

coxy ;D ;D 8)

[woodmills1]

keep the stove water at 195 and shorten the cycle time on the furnace
also check for drafts from doors or windows inside that may have your wife feeling chilly even though it is warm



now that I have been in 8 winters of nice warm OWB free heat I feel chilly when the hose is 5 seconds away from demanding heat



so, also look at your thermostat to see if it is letting your house get just a little coller for just a little too long



getting spoiled by nice cheap heat makes us be  like








movie stars, kardasians, hiphoppers



nah we are just warm and spoiled

[NH4000]

Can you tell us more about your heating setup? What kind of radiators, insulation level of the house, open floor plan or lots of rooms? Multiple zones?

If you are using a higher water temp than your system is designed for you would have shorter cycles. I don't have a wood boiler and don't know how the cycling works. With gas or oil, when you hit your water temperature, the fire stops instantly. How would a wood boiler end it's cycle?

For comfort, you might consider a lower temperature for your water, but run your circulators all the time. That is how modern high efficiency systems will operate, trying to match the boiler output to the heat loss of the building. Having the boiler run at a lower level for long periods is more efficient than starting and stopping the boiler for short cycle times. I assume the wood boiler is on all the time, so where does the heat go when the thermostat is satisfied.

You might be able to avoid the sensation of cold you get when your thermostat is about to make another heat call. Also, different thermostats have different ranges between the high and the low - the range between when the heat turns off and goes back on again.

Here is a good source of information for heating and heat transfer information:
http://www.heatinghelp.com/Forum

Another great forum.

Steve

[thecfarm]

Do you have baseboard or forced hot air?
My wife runs the thermostat. I just keep the OWB full.  ;D

[NH4000]

   doesn't water boil at 212  that's why I thought that I would be safe at 205

Water boils at 212 at atmospheric pressure, sea level. It would boil at a lower temp in Denver, on your stovetop. Your boiler will be pressurized slightly, so the water will boil at a higher temp. The problem you want to avoid is that if you do start to boil, your pressure will rise and trip the pressure relief valve. You should have one for safety.

If the boiler is connected to a makeup water supply, you will introduce "new" water to the system when it cools. You need a makeup water connection in case a radiator leaks and reduces the water level, you will need to keep the boiler wet so it can absorb the heat of the fire without cracking.

If you have a steel or iron heat exchanger in your boiler, introducing new water all the time will bring a lot of oxygen to the system, which will rust the ferrous components and can clog valves and pumps with rust. If you have water in an iron system for a long time, the available oxygen in the water will react with the metals until it is used up, then the oxidation stops. When I drain my heating system at home, I get greyish water, but never orange rusty water, even though I have a cast iron boiler, steel pipes, and iron radiators.

So, to make a short story long, you could conceivably mess things up if you go into boil, spit out water to relieve pressure, and then take in fresh water on a frequent basis.

I also think you would sense a greater contrast between running the heat and not running, and feel less comfortable.

[coxy]

Do you have baseboard or forced hot air?
My wife runs the thermostat. I just keep the OWB full.  ;D

I have both and do what you do :D

[Dusty Rhodes]

I am no expert, but if you have any pex lines aren't they rated at a max. 180 water temp? Not sure how much temperature the pex lines can actually take beyond that rating. At least thats what my pex lines say they are rated for.    My Heatmore System has an aquastat that shuts off power to my blower system if the water temperature reaches 200 degrees.  Personally I would not want my water temperature beyond 180 degrees.  If your cold inside that house with temps coming in the 180 degree range then something else is not right about your heating system or, your house needs some major insulation, caulking or both. Just for some perspective, water temps of 160 degrees will scald your skin with 2nd and 3rd degree burns in 1/2 a second. Thats hot water. At that temp you would not be able to grasp the pipe and hold onto without getting burned. My system is set to operate at 160 - 180 degrees and keeps the house quite toasty even on the coldest nights.

[r.man]

If the heat inside is running all the time without achieving temp then increasing boiler temp will help. If the inside is not running all the time turn up the thermostat. Not sure about gasifiers but I have boiled lots or water out of OWBs over the years for different reasons and have never hurt anything. 212 won't bother pumps pipes or coils. Not sure about baseboards or gasifiers.

[thecfarm]

NH4000 I don't think he has a pressure relief valve. I don't on my OWB,mine is a Heatmor. It's an open system,I think it is called. In my other house I had a pressurised system,relief valve and all.
And as r.man said,I use to have boil overs with my other furnace. It was not airtight and I would put too much wood in it.
The OWB I have now,I can put dead dry cedar in it,fill it up on a 60° day and I will not have a boil over. It smothers the fire out until the blowers come on. Really the only way to get oxygen into the fire box is by the blowers.

[NH4000]

NH4000 I don't think he has a pressure relief valve. I don't on my OWB,mine is a Heatmor. It's an open system,I think it is called. In my other house I had a pressurised system,relief valve and all.
And as r.man said,I use to have boil overs with my other furnace. It was not airtight and I would put too much wood in it.
The OWB I have now,I can put dead dry cedar in it,fill it up on a 60° day and I will not have a boil over. It smothers the fire out until the blowers come on. Really the only way to get oxygen into the fire box is by the blowers.

Are the blowers on a speed control or just on and off? I saw a guy who had a feedback controlled blower for maintaining temp on a smoker and it was pretty slick. The same principle applies to a wood boiler as fat as I can tell.
http://www.pitmasteriq.com/

When you say this is an open system, do you drain and refill it to prevent freezing? Is there a heat exchanger to keep the water in the heating loop separate from the OWB?

This looks like a nice setup and keeps everything inside.http://www.buderus.us/products/woodheating/g201wood-firedboiler.html
Anyone have one?

[thecfarm]

The blowers only comes on when the water temp drops down to whatever the lowest controller is set for.They blow ALOT of air into the firebox. No need to have it on a speed controller. I would want alot of air to get the fire going fast.With my system,I open the feed door and the fire looks just about out.But when the fans come on,the fire comes alive.
No need to drain it. I use mine to heat my hot water with. I burn alot of branches and real small wood in the summer months.But even if I did not,I would be using it for heat when it was cold,so I would be using the OWB when temps are below freezing.
I think my water circulates from the OWB to my heat exchangers. I use heat exchangers,but may have the wrong name. All they really are is just a car radiator with a fan behind it.

[NH4000]

The blowers only comes on when the water temp drops down to whatever the lowest controller is set for.They blow ALOT of air into the firebox. No need to have it on a speed controller. I would want alot of air to get the fire going fast.With my system,I open the feed door and the fire looks just about out.But when the fans come on,the fire comes alive.
No need to drain it. I use mine to heat my hot water with. I burn alot of branches and real small wood in the summer months.But even if I did not,I would be using it for heat when it was cold,so I would be using the OWB when temps are below freezing.
I think my water circulates from the OWB to my heat exchangers. I use heat exchangers,but may have the wrong name. All they really are is just a car radiator with a fan behind it.

If you had a speed controlled fan, you could control it off the return water temperature so that if you were putting more heat into the house - dropping the return temp - you would put more air into the fire. The fire would burn at a fairly even rate and the heat would always be on.

When you say a car radiator, you are describing a forced air system or do you have hot water radiators in the house?

What do you do if the power is out and your fan isn't on? Or a vacation? How is freezing prevented?

[thecfarm]

When the fans inside the OWB comes on it drives ALOT of air into the fire box burning the wood. When it reaches the high temperature about 190° the fans turn off and the fire is smothered out. As I said when I open the door the fire is just about out. That's why I can burn dead cedar and have no worries of a boil over. When the water drops to about 180 the fans come back on again and gets the fire going to heat the water back up to 190. Than turn off again. I would have no idea how many times in a day the OWB cycles.It's a very good system. With this OWB,it's really a whole diffeant way to burn wood.
I have one stand alone heat exchanger in the basement.
Like this.


 

Than I have another one just like the one pictured,but with no fan that is in the platium of my FHA system.
Power goes out,genator gets started. I have a gentac box and I only have to flick 4 switches in the basement to get that going. But we don't lose power for long. Sometimes I just open the door of the OWB to get the fire going. Most times we only lose power for 4-6 hours.
I have a friend that has filled the OWB when we are away.
The circulators run all the time.
This is the back of my OWB.



 

I did not install any of this. I only did the grunt work. Dig the drenches,put the electical in the treaches,put the pex pipe in,hang the heat exchanger,cut the holes into the basement.

[coxy]

forgot to say I am heating two places with it to

[Sonofman]

Coxy, if you do not have your coil on your forced air system plummed correctly, it can make a big difference. Looking at cfarm's picture, the hot water comming from your boiler should enter the coil on the air leaving side, in this case, the top fitting. The thicker the coil, the more the passes, the bigger a difference it will make. When I put mine in last fall, I had the lines marked backwards. I got them right this fall, 25 to 30 degrees hotter air with everything else the same. In commercial HVAC units, I have see as much as a 50 deg difference between backwards and right.

Of course, this can make getting the air out of the coil a little challenging sometimes.

[homeyd]

i disagree ..the hotwater from the boiler should always go into the bottom of the coil weather its horizontal or vertical,as with any hot water systrm ..steam is the only one tht enters the top first . imo

[r.man]

Can't imagine it making any appreciable difference in a fan forced system.

[beenthere]

I'm thinking the fan just moves air away.

The hot water coming in low and naturally wanting to rise means the water pump doesn't have to push it against its natural flow direction. Can't fight the laws of physics without losing some ground.
i.e. Go with the flow.  ;D

[AsaG]

In addition to what has already been posted...

The supply entering low allows for more complete purging in low pressure, medium flow systems.  Coils usually are internally plumbed with multiple tubes in parallel so as not to restrict flow.  If the coil isn't purged completely, water may not flow through all of the "circuits" within the exchanger resulting in reduced heat transfer.  In refrigeration systems, it's common practice for the refrigerant to enter the air/fluid exit side of the exchanger.