Central Boiler 760HDX - Montana

[DDW_OR]

Why you clean it out?

How due the Heat exchangers in the back look?

having trouble getting the chamber to 100%, usually 75%
so since the fire was out, decided to do a partial cleanout
could not remove the Tubrolaters. so will try again next time
forgot to take photo
have plans in 2023 to extend the leantoo, to be over the sawmill, Fire Wood  processor, and firewood

[PoginyHill]

In my experience, less dry wood will lead to poor reaction chamber performance. A good bed of hot coals will help.

[Rhodemont]

I completed the installation of a Heatmaster G7000 in October.  Did it all myself with a few phone calls to the dealer and plumbing supply.  Toughest thing was working with that insulated PEX tubing pipe, it was like wrestling a bull.  It is now heating the house and workshop off the barn.  Next year the old garage/barn will be coming down and a new timber frame raised.  The second circulating loop on the G7000 will go to the new garage.  The currently operating heating loop goes to a 70 plate heat exchanger just above my Viessman oil boiler.  A pump circulates through the heat exchanger to the oil burner keeping it hot all the time so it does not need to fire.  This heats the domestic water, first floor radiant heat, and second floor base board plus a zone going out to the shop.  The Viessman has gone off a couple times because it is computer controlled with outdoor sensors, ramp up /down curves, and day/night settings.  I have been adjusting all these settings so the Viessman does not sense the temp drop in the evening and fire to ramp up the slow to reacting radiant heating.  And also not to fire fire in the morning when it wants to get ready for domestic hot water use.  Years ago when I installed the Viessman it took a couple months to get all the setting just right.  Once it was running I removed the Consolidated Dutchwest wood stove from the fire place hearth.  For the past 36 years that was the primary source of heat for the first floor burning abut 5 cord/year.  In it's place for some heat and ambiance I installed a Jotul Sebego gas stove.
Still have more to learn but so far everything is going very well.

[beenthere]

In my experience, less dry wood will lead to poor reaction chamber performance. A good bed of hot coals will help.

Is that "less-dry wood" or meaning "less dry-wood" ?   ;)

[PoginyHill]

More wet.  :laugh:

[Dan_Shade]

Do any of you use creosote sticks or powder to assist in outdoor boiler cleaning? 

[PoginyHill]

I do not.

[trapper]

soda cans

[DDW_OR]

soda cans

please explain how burning aluminum will help with creosote

[beenthere]

Have heard of that trick, but didn't see any effect when I tried it. 

Googled, and read this:

In fire tests conducted on aluminum materials, it was found that when fire temperatures exceed the melting point (which occurs at a range of 600-660°C), aluminum surfaces that are exposed to the fire can melt, but do not burn.  Heating the cans causes an increase in heat in a chimney which can help prevent creosote from building up on a clean chimney. However, aluminum oxides are very stable and do not react to high temperature. This means that there will not be much of an impact on built-up creosote.     

[DDW_OR]

found that the furnace was not burning correctly
every time i closed the firebox door there was a "Roar" from the air box
last time smoke came out of the air box.

so i opened the exchanger door on the back
the turbulators where completely plugged with creosote
removed all of them, then used the propane torch "weed torch" to burn the creosote off
then scraped, then burn, then final scrape
the creosote also glued the door insulation to the exchanger
plan to get some roofing flashing to place in between the door and the exchanger
not connected to either one except by friction.





 


 



 

[beenthere]

What is your conclusion about reason your creosote build-up happens so quickly? 

My guess is wood too wet.

[DDW_OR]

What is your conclusion about reason your creosote build-up happens so quickly?

My guess is wood too wet.

the softwood i am burning is from live trees that blew down 2 years ago.
so the moisture content is low, but the sap content is high

[Ianab]

Not sure on your boiler design, but softwoods will generally burn OK with a hot burning fire, but all sorts of smoke / creosote if they are dampered down too much.  We don't run the larger wood boilers here, just smaller inside wood burners. But a good method with pine etc is to only part load the fire, and let it burn a smaller but hot fire. You have to feed it small amounts more often of course, which is easy if you are sitting beside it in the lounge. Stacking the fire full, then closing the damper can cause problems. 

I don't know if that applies to your situation, but is it possible to run some small loads during the day to get the heat up and burn off some creosote? I'm just thinking the dry softwood flares up into a hot flame, the boiler senses it has enough heat, and damps the fire too much, to a smouldering creosote maker. 

Other option would be to mix of wood in some slower but longer burning woods.

[DDW_OR]

Good advice for a standard furnace 

But this is a computerized down draft furnace 

 

[Ianab]

But this is a computerized down draft furnace

Can the operating parameters be tuned to better handle the softwood? The fact that the parameters can be adjusted suggest there are reasons you might want to adjust them. 

Also is the amount of air for the "low" cycle adjustable? This would run the fire a little hotter during the low phase, but not so much that it overheats or never switches to the high burn. 

Really just thinking out loud here, as I've never had experience with this sort of unit.  But the computer should be able to do similar sort of adjustments to the fire as a person tending it manually would, and because all wood isn't the same, the adjustments should vary according to the fuel used. 

[DDW_OR]

Yes the settings are adjustable.
i am waiting for this load of wood to finish. then i will inspect the exchanger

looked at the burn history today. every burn got to 100%

[DDW_OR]

storm warning
snow accumulations of 2 to 5 inches with higher amounts near Flathead Lake

so am going to the furnace to re-load and inspect

Heat exchanger is nice and clean. will post how it is in late January



 

[PoginyHill]

That creosote building is certainly not right. I have the 750 (no turbulators and no refractory cylinder in the reaction chamber). Essentially the same operation as yours. I have never had that much build-up, even when I burned less than ideal wood.
My suggestions:

• Reduce the differential to 10 deg
• Raise the setpoint to 190
• Load only enough wood to last about 12 hrs

If you load too much, it may not allow the fire to get hot enough. This is how I operate mine and have never had creosote problems on the exchanger.

[DDW_OR]

I have a 750 in Oregon 
See my first post 

[Dan_Shade]

I've been running a 760 since mid November, with mostly green wood. 

Over the past few days, the stove wasn't running efficiently, would not stay over 50%

I opened the back up to clean out the heat exchanger area, the turbulators are a pain to get in and out, mine weren't as bad as the pictures above, but I spent an hour or so scraping and cleaning all together (with a break for lunch). 

When I closed it up for lunch, efficiency jumped to 80% before it came up to temp.



 

[DDW_OR]

since i removed all of the turbulators the burn has been at 100%

i will never put them back in!!!!!!!

[PoginyHill]

DDW, has the creosote build-up also resolved itself without the turbulators?

[DDW_OR]

DDW, has the creosote build-up also resolved itself without the turbulators?

Yep.

https://forestryforum.com/board/index.php?topic=124171.msg2026577#msg2026577



now i have to re-do T1 from 2 to 8 ft deep