Furnaces for diy central heating

The next form of diy central heating that we will look at is a furnace type with duct work. This is usually a furnace that can be gas, electric, or oil.

heat furnace

It has heat ducts going to each room in the house and usually has an air exchange system to bring air back to the furnace.

heating diagram

Metal ductwork was pretty much the main type of venting material used for a long time, but now it’s quite common to see flexible ducts. Flex ducts are much less expensive than metal and a lot easier and faster to install.

They can be installed right into the floor joists, rafters, and crawlspaces. The trick is to get a good tight fit so that air doesn’t escape.

It’s really important that the flexible heating and cooling ducts don’t get twisted or pinched. Most types are quite strong, but bending does happen.

heating ducts

The air-conditioning system can be included in the heating ductwork. It is usually run this way to save materials. The picture shows some examples of air conditioners.

Air conditioners can be central or local. A big AC system using air ducts would be a central system. Smaller units in each room would be local air-conditioners. The decision of which to use depends on the local climate.

hvac diagrams

Furnaces can be a complicated aspect of the heating system. Some do it your selfers get overwhelmed and need to call heating repair contractors. There’s no shame in that. But if you decide to brave the project on your own just remember that most heating systems use 240-volt circuits. Be sure to disconnect the power before doing any work on heating and AC systems.

It’s not enough to shut the breaker off. You should put a piece of duct tape over the breaker and communicate to all family members what you are doing. If you’re removing an old system, remember that the old wiring might need to be upgraded to supply the demands of a new appliance.

top of page

Next, radiant floor heating

Back to heating main page

Over 4 million visitors to this site since it was born!

My newsletter keeps you up to date on home construction and design ideas.

home construction

I just wanted to say that I love your website. My husband and I followed your instructions on building our own home. Most of the work we did ourselves, but not all. We saved $90,000 in labor costs and now have a beautiful home that we own.

--Sue and Les Carrigan, Draper, Utah

I built my own home doing all my own labor. My house costs me around $70,000 for materials. It took me 8 months to build and is about 2,000 square feet. I didn't think I could do it, but your house web site encouraged me. I used all the info you had.

Thank you,

Benny Luis Lopez,

Gainsville, Florida

I can't thank you enough for your free information web site about home building. I was looking for Electrical wiring diagrams when I found your site. It was very helpful.

Steve Lundquist,

Little Rock, Arkansas

My wife and I lost our home to foreclosure but we kept a plot of land to start over. We are halfway through the construction of our house. Your website gave us hope to start over and build a house with low payments. We are in our late 60's but we find it rewarding to put so much effort into a project that will reward us for years to come.

Name respectfully withheld