Last Fall (October 2007), we purchased and installed a Greenwood Model 100 indoor wood-fired hydronic furnace. It has been a terrible experience. So terrible in fact, that we’ve created a website to warn others about the problems they can expect from a Greenwood Furnace. Here’s our story:

 

We wanted to burn wood for heat not because we were interested in saving money, but because we wanted to be “carbon neutral” and reduce or eliminate fossil fuel dependence.

 

Before purchasing a wood fired furnace, we did extensive research into a wide selection of indoor wood-fired hydronic furnaces:  Wood Doctor, Tarm, Eko, Garn, Alternate Heating Systems, Greenwood and many more.  We spoke with many manufacturers and dealers and traveled great distances to inspect actual units and, whenever possible, see them in operation. We did our homework!

 

We finally chose the Greenwood Model 100 because Greenwood claimed--on their website, in their brochure, and through the mouths of their sales people--that “it is safe to operate, burns smoke and creosote free…” and is “…as safe to operate as a home water heater.”

 

Don’t believe it. It is not so. 

 

Our Greenwood furnace has caused us major smoke and creosote problems. The neighbors have complained bitterly about the smoke and the town has issued us a cease and desist order.  Greenwood Furnaces, Inc. has been uncooperative. We sincerely wish to “go green,” but with an unusable wood-fired furnace and no resolution assistance from the company that sold it to us, we may be forced to return to oil heat this coming winter.

 
If the website link did not work, here is our site: www.greenwoodfurnace-warning.info
Please check us out!

I can't tell you how close we have come to buying an indoor hydronic furnace, but heard to many horror stories. We did have a Jotul in our last house and burned all the time while I grew up. I have to ask, what kind of wood did you burn, dry hardwood? Did you keep the fire hot? I know many people tend starve the firebox of air to lengthen out the burn times or slow the heat output, but if you do that regularly you will end up with lots of smoke and creosote. The only time we saw smoke was on start up.


Again not that I am saying you did this, I am more curious then anything else. I would think if you have a water jacket around the fire box it couldn't get hot enough to reburn the smoke and would cool the exhaust gasses down so they are way more likely to deposit creosote.

Are there any good hydronic indoor wood burners?

I self-installed indoors a Tarm Solo Plus 40 (140,000 btu) gasification wood boiler in summer 2007 and used it all of last year's heating season. My satisfaction is 98%. It replaced my old water jacket OWB. While there are circumstances that will result in some smoke, there was no major smoke and no creosote problem. I burned only dry pine, never had to clean the chimney until the end of the heating season, and no creosote buildup anywhere. The conditions during which some smoke will be produced are on startup, which lasts about 15 minutes, and in fairly unusual burn conditions, which are self-correcting and can be largely avoided. This system is amazingly efficient, and I have no issue with recommending it. I am a user only, not a dealer, rep, etc. I have prior experience with a water jacket OWB as well as indoor wood stove. We heat exclusively with wood (electric backup) and have done so for 18 years. 2007-08 heating bill (electric) for us was $200.00.