Is this common for comfortmaker plumbing

alby42

The image speaks for itself. Is this common to leave the air intake open on this type Comfortmaker heating unit? It is gas fired and I have a model number somehwere if it helps..I believe it's install date is mid 90's!

Jean-David Beyer

I am not sure.

My Quaker Meeting had two of those things. They looked just like the one in your picture. They may have lasted 10 years or so, when we got too many pinholes in the heat exchangers. We replaced them with Rheem ones that had far far better heat exchangers.



Part of the trouble with the Comfortmaker ones was that the original contractor did not know how to properly twin them. (In fact, he should have set them up one for each heating zone.) He just had them pull cold air from the return plenum and had them both blow into the supply plenum. So if both rooms asked for heat at exactly the same time, and everything else was equal, both blowers would start at the same time, which hardly ever happened. Otherwise, one would run backwards and burn out after a while.



The burners were lousy. They were tubes with slots punched in them. Plain old steel, and they rusted over the summer, so you had to take them out and remove the rust with a wire brush; sometimes you needed a screwdriver. I thought of having them nickel plated, but never did. They should have been ashamed of the heat exchangers: two pieces of pressed metal spot welded together. The burner was pressurized so any leaks in the heat exchanger meant the exhaust gasses passed through the heat exchanger into the building. Before we replaced those units, the new contractor tested the CO level in our building and it was somewhat unsafe. And our building is very leaky.



The next contractor did not know to clean the inside of the heat exchangers each year, so at one point I noticed one of the 5 airways was plugged in one of the furnaces. He had never cleaned them and I never knew he should. So we got rid of that contractor and got the next. One knucklehead after another until we got the present contractor. We had him replace the ductwork first (it went in a crawl space that was really too small to work in). The building is almost 200 years old and was not originally heated. That helped a lot. The new ducts were large enough, and insulated. Also, we did not twin the furnaces but had two zones which is very important to us, since we do not heat one zone at all except on Sundays. The other we keep at a minimum of 50F when no one is around so the pipes will not freeze. Furthermore, the little ducts were elephant trunk hoses that the original contractor just pushed over where they connected to the registers. Many had fallen off, so we were cold and the groundhogs were warm.



A year or so after that I noticed the flames were misbehaving, so we got that contractor in and they recognized the problem of leaks in the heat exchangers. So we replaced those furnaces. The comfort maker had provision for running in external air supply, but ours did not use that.



There are more and more tales that could be told about that building. That is when I started learning about heating and heating contractors, and knuckleheads.

Tim McElwain

It is possible that some

equipment can get its air for combustion from the room in which it is operating as long as the return air is not coming from the same room. I would need to have a model number and look up the specifications and venting instructions to know if this unit can be hooked up this way.