On 1/24/2010 15:56, ransley wrote:
On Jan 24, 11:46 am, wrote:
I'm trying to determine the pros and cons of having a wood boiler
installed on my property. If you haven't heard of these, the boiler
is built to circulate water around the firebox. The water gets pumped
into a heat exchanger which is located in the main heating duct of the
house. The existing indoor furnace pushes the air around the house.

Anyway, I'm looking at a Heatmor boiler, and I'm now looking for
people who have experience with these. The website says that the
boiler has a forced draft fan (75 cfm). It also says that the boiler
can heat a 3000 square foot house. I know a little about combustion,
and I calculated that with 75 cfm, you cannot burn more than 10 lbs of
wood an hour. And if the wood is 45% moisture, then the available BTU
is around 40,000 BTU. A 40,000 BTU furnace is very small for a 3000
square foot house.

So, has anybody dealt with these Heatmor furnces? Can you tell me
anything about performance and maintenance?

thanks,
FB

If boiler is outside full of water , you must put antifreeze in the
water, antifreeze doesnt transfer heat as well as water, is that
included in their btu output calculation. Do you have to feed it every
hour that would become a hard full time job

Those boilers were pretty popular in my general area for a while.
Unfortunately they got a bad reputation because folks were buying them
based on price only. The "big box quality" versions have essentially a
huge steel firebox with a coil wrapped around the outside and a small
motorized damper. The idea being you would stuff it full of wood to last
all day and when your stat called for heat the damper would open. Since
the wood was in contact with the steel it gets cold. So the unit belches
dense acrid smoke for a really long time until it heats up.

I border on a less densely populated area and the nearest ones I have
seen are a mile from here. They make such heavy smoke that on a calm
morning it is like driving through fog. Most municipalities here have
now banned them. The heatmor that was mentioned is probably the best of
that type system. Their is a firebrick liner and it has an induced draft
so there is less smoke. Unfortunately the "big box quality" units killed
off all installs.

Installers typically haybale the install. They don't use water-water
heat exchangers and just tie in directly and don't use antifreeze.