Draft Inducer motor question for furnace techs

[Blue_Goose]

Have a Lennox G26 Furnace. On New Years Eve I was getting concerned as the motor was making a clicking noise and getting very warm /hot to the touch. Tech came out and said motor was overheating and replaced it to the tune of 500 bucks (150 dollar part and 4 screw installation mind you).

Well the new motor is doing pretty much the same thing though not clicking as bad (I think it is water causing the noise)and it gets just as hot.

I still have the old motor and he is coming back out today to check things out


All that to ask this question. Does the draft inducer motor play any part in how much hot air that the furnace puts out or is this strictly a function of the blower/fan? Reason I'm asking is because I am happy with how quickly my home warms up now and was wondering if the draft inducer motor is playing any part in this. My guess is no as its function is to exhaust?

Can anyone shed some light on this? If it is playing a part in how efficiently my home is heated I may leave well enough alone and eat the 500 (or have him put old motor back in and replace it myself for 150 bucks)

Just confused a bit and want to understand what role the draft induce motor plays

fwiw he put a yellow thing on the wires and the old motro read 1.3 where the new one said 1.8


Thanks


Goose

 

[brianl703]

If the inducer fan fails, there's a sensor that turns off the burners.

The motor normally runs pretty hot. The flue gasses are hot. Might have something to do with it?

I wouldn't expect the draft inducer fan to have much of an effect on how much heat the furnace puts out...unless it fails..then it won't put out any heat at all.

 

[fsskier]

You pretty well have it. Older furnaces had a lot of waste heat to keep the chimney drawing well. This downside of this is not only heat loss, but also the draw could vary a lot depending on wind direction, other gas appliances sharing the chimney, height and much more.

Now ideally you inject an exact amount of fuel and air for complete combustion, too much of either leads to reduced efficiency. Your inducer motor/fan etc is all sized and designed to feed in the "perfect" amount of air - providing that all is working correctly.

The hot air blown into your house from the heat exchanger is an entirely different operation.

We need a Lennox tech here to tell us how hot that motor should run!

 

[bepperb]

Either the draft inducer works well enough that the combustion chamber doesn't get too hot and trigger the limit switch, or it doesn't. So I wouldn't worry that a new fully functional one would change the way the heat is output.

If you have two fairly working ones, I wouldn't worry too much. It should be something you can do yourself, just getting the right part, and the part itself, can be frustrating if you're not a HVAC certified person.

How hot is hot? Can you hold your hand on it?

 

[Blue_Goose]

Thanks guys...HVAC techs were just out here and they replaced the newer inducer motor with the old one. Thankfully I still had the old one..

Just ran a test and house heated up pretty quickly with the old inducer motor back in there so everything seems fine and I'll have 500 bucks back in my pocket. He even said that the rattling noise I hear now and then is normal as it is a bit of water that sometimes will get in there (I heard it with both inducers).

Hot I mean Hot, no you can't put your hand on it for more than a second or youch...again both the old motor and new motor did it. I attribute the replacement of it due to a tech that probably had not come across this situation before and figured it was overheating and needed replacing.


No harm no foul. They are a good HVAC company and I'll use them in the future. They responded to my concerns and thats all you can ask for.

I know going forward if it does fail how to replace it at a LOT lower cost than 500 dollars

Goose