Heating, Air Conditioning, Fridge, HVAC/Heat/ac issue


QUESTION: I have a furnace. And the previous owner built an extension. It seemed there's an additional fan/blower to blow the air to the that extension of the house. Right now that fan is continuously running. The previous owner says this fan is wired to the furnace. What are the possible issues that could cause this to happen and what are the possible fixes and cost?


Without seeing your system, I will have to tell you what I think you might have. Instead of making sure the furnace and A/C were large enough to supply the extention, they just cut a hole in the existing duct work and ran new duct to the extention. When they saw this wasn't working, they decided to add a fan to the new duct work. Of course this is completely wrong way to do this.

Now on to the question, again I'm just guessing. They probably ran power out of the breaker box to the new fan. Then ran a thermostat cable from the furnace to the new fan. Installed a 24v relay to start and stop fan when the furnace fan stops and starts. It could be that the relay is stuck in the closed position.

If my assumption is correct your looking at $120 to $250 for someone to come out to service it.

I am located just outside the KC area and I do service the Kansas side.  Let me know if I can help you.

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QUESTION: It was working fine before. I've lived in this house for 6 years. I want it fixed I just don't want a huge bill and shocked about it. It's got to be the reason why I have a200 dollar electric bill. I'm going through a nasty divorce and haven't received my first alimony/child support check and living off my mom right now so I just don't want to rack up her bill


I agree that running the fan 24/7 will jack up your electric bill. The only thing that I can suggest is to find the breaker to the fan and turn it off. Let it run with just the furnace fan and see if your house is still comfortable. Then you could have it repaired later.

This should be an easy fix for a good service tech. I wouldn't expect it to be a huge bill.

Let me know if you have any other questions.

Heating, Air Conditioning, Fridge, HVAC

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Jim S.


I can answer questions on gas or electric furnaces, ac units and heat pumps. I don't work on boilers,chillers,or home appliances.


I have been in the HVAC trade for over 35 years. For the past 15 years I have owned my own business. I am semi-retired so I can answer questions in a timely manner.

I attended trade school for 5 years on weekends and evenings. This was very hard to do, but well worth it!

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