Sizing a wood furnace

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battelro

New Member
Oct 24, 2022
2
Cass City, MI
Hi.

I want to buy an outdoor wood furnace. My local dealer sells CleanFire models. The dealer quoted me a CleanFire 500, but when I went to the website, I saw that there is a CleanFire 300 model. The difference in price is $2,900. My house is about 1500 square feet. It is well insulted (foam spray on). I'm wondering if the 300 model will be sufficient to heat my house.

TIA
 
You would need to do a heat loss calculation to be sure. If your home is well insulated and 1500 square feet, I doubt it's more than 50K on the coldest day. I would think the 300 would be OK. Also be aware the BTU output ratings are for only one moment in time. The unit likely puts out roughly half the 150K averaged out over an 6-8 hour period.
 
My next question is the opposite. I’m not sure the 500 is big enough. There will be times that I’m gone from 7:30 am til 10:30 pm. No opportunity to come home. On a frigid Michigan day, is that too long to be away?
 
My next question is the opposite. I’m not sure the 500 is big enough. There will be times that I’m gone from 7:30 am til 10:30 pm. No opportunity to come home. On a frigid Michigan day, is that too long to be away?
Personally I’d pass on any product built by Central Boiler. Search on YouTube for videos on how to clean the HX, what a horrible design. Your dealer is clueless also. I’d find a new dealer and brand.

Gasification boilers are meant to be run balls to the walls. The harder they are run, the more efficient they are. By getting the next larger boiler, all you are going to do is makes lots of creosote.

If your house is as well insulated as what you are saying, the payback on a OWB will be really far out in the future vs a HP, or gas. If it’s more a self sustainability thing, I get it.
 
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