Setting Up The Wood Boiler

This is a continuing story of how we designed our own wood heat system to warm our house and keep the mess outside. This old farm house was never warm. A staircase in the living room let all the heat go right up the stairs.

We used to heat with a wood stove in the kitchen but switched to gas when we found out the chimney was bad. Even with the gas heater, it still was not warm in the house.

The first $440.00 gas bill for the month set me in motion to heat the house with wood again but keep the mess and fire outside keeping the house clean and safe. I moved an old inside wood boiler that used to heat a chicken house that I had traded $200.00 in labor for, into place about 70 feet from the house.

This boiler had the pumps mounted on the boiler and was designed to be used in a pressure system.

Converting Wood BoilerTo Outside And Hooking Up

After mounting the boiler securely on some railroad ties embedded in gravel. I proceeded to convert it to outside use. The old pumps and plumbing was removed and the input and output located. I first hooked up to the top of the boiler to go to my pump because the water is the hottest there. That was a mistake!

Every time the boiler would get too hot and make steam, I would lose my prime on the circulating pump and circulation would stop.

It is essential to take the input off the bottom of the tank and feed it to your circulating pump.
That assures that you always have water in contact with the pump so no air will get in.

We are now working with what we call an open system. The vent on the top of the boiler that used to have a steam pressure blow off valve is now open to the atmosphere. When the boiler gets too hot and makes steam, it goes out that hole in the top of the boiler into the atmosphere, eliminating the danger of a steam buildup and explosion.

One inch pex pipe is used to make the connection to the distribution piping in the house. It takes one line in and one line out. The circulating pump is located in the house and the pump needs to circulate constantly in below freezing weather so things won't freeze up. The return line takes the return water from the house back into the top of the boiler.

In order to connect the pipes from the boiler to the house without freezing., I buried a 6 inch SD35 sewer pipe between the boiler and the house that I fished the smaller 1 inch pex pipes through. Then I covered the sewer pipe with sawdust to insulate it. There are pipes available for $10.00 a foot or so with insulation built in but sawdust is a whole lot less expensive.

It was necessary to go through my wife's chicken coop to get to the house, so we left the 6'' pipe exposed to let a little heat escape into the coop to keep the chickens warm.The boiler was insulated by placing 6 inch unfaced fiberglass batts over top of the boiler tank and covering them with a heavy duty vinyl tarp wired around the bottom of the tank to keep it in place.


Where the pex pipe came out of the sewer pipe, I added foam insulation pipe to the individual lines and enclosed them in flexible black drain line and sprayed polyurethane foam around the ends to keep rats and mice out of it.



Entering the house through the cellar wall meant breaking out one of the blocks and putting the 6 inch pipe through. Mortaring around the sewer pipe keeps the animals out. This is important as mice fine the warm sawdust attractive and you don't want them to have a way into the house.

The sewer pipe is buried where it goes through the chicken yard and covered with sawdust for insulation. Picture shows indentation where sawdust has settled.A great pile of wood---about 30 face cords---is ready to keep us warm this winter.


In our next post we will tell you how we hooked up on the inside to the pump and distribution system.