outdoor furnace

[wertach]

I have been considering an outdoor furnace (wood). I have a heat pump, but I also have a lot of wood that would probably run it most of the winter just from the limbs that fall off. I was wondering if any of you have any idea which one to go with, and questions to ask? Dependability. long turn problems? They are all kind of vague about price and say they need to do a site evaluation. Before I let the "salesman" in the door I want to know what to look for.

[key]

BEWARE!

I only say this because I have been called in to solve many of wood boiler problems. The biggest mistake I have come across is that inexperience "sellers" of FREE HEAT appliances, over size the wood boiler.

I would suggest that you ask the following Questions to your future contractor.

- References

- Thermal dumping in an over heat situation

- is a primary loop neccessary

- is a bypass neccessary

-condensation and soot issues in the chimney

You want a unit that will burn...you don't want a unit that will constantly modulate the combustion air in the fire chamber.(do to over sizing)

Also KNOW THE BTU capacitity of the wood you are planning to burn..

[karsthuntr]

You will use 2-3 times the wood of a normal inside wood stove, this will be okay if you don't have to buy any wood. I hope you don't have close neighbors, they smoke a lot.

They do work good though. I would make sure you have HVAC guy check out the wiring and the coil install before you start the system. The guys around here that install the wood stoves, install coils the size of the existing duct and not the ones that fit the required airflow. If I were you I would make the HVAC guys do all the control wiring.

Make sure they insulate all pipes underground and inside the house, this will save a lot of wood if they are insulated.

You can not let the wood stove go out, there are no provisions for antifreeze. The woodstoves are an open system and any anitfreeze will boil off.

[key]

Originally posted by karsthuntr
You will use 2-3 times the wood of a normal inside wood stove, this will be okay if you don't have to buy any wood. I hope you don't have close neighbors, they smoke a lot.

They do work good though. I would make sure you have HVAC guy check out the wiring and the coil install before you start the system. The guys around here that install the wood stoves, install coils the size of the existing duct and not the ones that fit the required airflow. If I were you I would make the HVAC guys do all the control wiring.

Make sure they insulate all pipes underground and inside the house, this will save a lot of wood if they are insulated.

You can not let the wood stove go out, there are no provisions for antifreeze. The woodstoves are an open system and any anitfreeze will boil off.




I like the points that Karsthuntr has given...so what can be learned from this advice?

Deal with a HVAC guy who knows controls and hydronics.

DON'T deal with a seller of FREE HEAT appliances...

[simpleman]

Originally posted by key
BEWARE!

I only say this because I have been called in to solve many of wood boiler problems. The biggest mistake I have come across is that inexperience "sellers" of FREE HEAT appliances, over size the wood boiler.

I would suggest that you ask the following Questions to your future contractor.

- References

- Thermal dumping in an over heat situation


Key, you bringup a very important issue here.I just install a wood boiler for a customer a couple weeks ago and all the
heat these high mass stove can put out you really need to have a place for them btu to go.If you are dealing with a home that is built tight then a wood stove should be out of the question.


I'm going back this week to install a storage tank and use it has a buffer as well.
One must realize that wood boiler have very little controls built into them to give one automatic control.

From what I'm seeing either you better put forth some thought that the owner is going to have to do some kind of manual/watch control.

We were going to use the pool for a dump zone but with wiring a bypass controller for the pool pump and another
aqustat to control that and yet another priority relay it
becoming a endless project.I must say yet a learning one.

Storage tank is a must!!!

[key]

A POINT OF INTEREST!

The best wood boiler installation I have ever seen, was a simple design...

- Ordinary wood boiler...

- Infloor heating...

- Run boiler for 8 hours, every 4 to 5 days...

- Install an old milk-tanker as storage...

[karsthuntr]

See these news reports:

http://www.times-news.com/siteSearch/apstorysection/local_story_289092845.html

http://www.times-news.com/siteSearch/apstorysection/local_story_281112853.html

[johnsp]

I've seen outdoor boilers, not furnaces. There are indoor furnaces that you could tie into the ductwork of the house, but now you probably need a seperate flue for the unit. I say keep it simple and just get a wood stove.