Outdoor Wood Furnace Info

All-Purpose OWF Discussions => General Outdoor Furnace Discussion => Topic started by: lindnova on February 27, 2014, 06:26:01 AM

Title: How much cooling with boiler fan running and wood out
Post by: lindnova on February 27, 2014, 06:26:01 AM
How much do you think the burner fan cools the outdoor boilers if they run out of wood? 

I have a Heatmor 200 with the forced air fan.  When it runs out of wood the fan continues to run and the propane furnace will kick in and allow heat into the pipes to circulate and prevent the outdoor unit from freezing.  I rarely happens, but in this cold weather if I don't have enough wood in and end up working late sometimes it is out for a little while.  Usually not enough for the propane to even kick in - water temp 120-130 for example. 

If I were to leave for a weekend I have wondered if it would be better to heat the house warmer, shut down the outdoor furnace, turn down the house thermostat and let the propane go on when needed,,, or just load full with good wood and take the chance that it might run out and the fan might be cooling for a while with the propane on.

I would think in these cold temps we have now near zero if I warmed the house to 75, turned the temp down to 57 and left, a full load of wood would last over 24 hours no problem. 

Anyone have experience or thoughts?
Title: Re: How much cooling with boiler fan running and wood out
Post by: ITO on February 27, 2014, 06:39:22 AM
 I installed an aquastat on the supply line, it shuts off my draft fan if the supply temp drops, it also saves the coals, the embers will remain for quite a while and when we get home, reload and throw a bypass switch, the draft fan ignites the wood from the coals left. This has worked well for years for us, the coals that are left keep some heat in the boiler water, not sure how long that would last in exceptionally cold weather but it works for the short haul.
Title: Re: How much cooling with boiler fan running and wood out
Post by: slimjim on February 27, 2014, 06:52:40 AM
Great solution Ito, I thought that I was the only one promoting that theory.

        LIKE BUTTON?
Title: Re: How much cooling with boiler fan running and wood out
Post by: Sloppy_Snood on February 27, 2014, 08:11:26 AM
^^^ LIKE THIS  :post:
Title: Re: How much cooling with boiler fan running and wood out
Post by: lindnova on February 27, 2014, 08:19:07 AM
That is an obvious solution.  Great idea.  I think I will hook one up.
Title: Re: How much cooling with boiler fan running and wood out
Post by: rick n kristi on February 27, 2014, 09:22:24 AM
If I'm going away for a long time I throw the bypass in the water circuit and turn the boiler temp down to 160. This stops the house from taking any heat from the boiler but allows the water to circulate through the lines to the basement. I leave the pump running and leave the fan operational. On a full load of well seasoned wood with a little bit coal mixed in the boiler will remain at temp for a week in normal weather (or longer), in these sub zero nights I have gone 4 days and returned to a boiler at temp and enough coals to fire it back up with a new load. I turn the house down to 50 and let the propane do the lifting while I'm gone.
Title: Re: How much cooling with boiler fan running and wood out
Post by: MD20/20 on February 27, 2014, 09:41:32 AM

Could you post some pictures of your modifications to the 325G to burn coal better?
Thanks
Title: Re: How much cooling with boiler fan running and wood out
Post by: ffbare on March 02, 2014, 08:51:59 PM
Ito great idea I will definitely set that up.
Title: Re: How much cooling with boiler fan running and wood out
Post by: ffbare on March 02, 2014, 08:53:42 PM
I just thought of something if I get a Ridgewood umm yeah I won't be able to do that  :(
Title: Re: How much cooling with boiler fan running and wood out
Post by: andyhowardcity on March 03, 2014, 06:00:32 AM
You should be able to ffbare, I have a similar set up and I think it would work for me. 
Title: Re: How much cooling with boiler fan running and wood out
Post by: ITO on March 03, 2014, 06:59:30 AM
I just thought of something if I get a Ridgewood umm yeah I won't be able to do that  :(
I'm not sure how the Ridgewood is setup so maybe the method would have to be modified?



Title: Re: How much cooling with boiler fan running and wood out
Post by: fryedaddy on March 03, 2014, 12:35:29 PM
My stove is setup more like a batchburn. I have 600+ gallons and use a timer.

My Aquastat runs the stove but I set a timer on 4-6-8 or 12hrs and pack the stove.
Once the timer has tripped my blower no longer runs.