My heater won't come on by itself when its cold outside. It would work fine when is was sunny or above 50 degrees. I could get it to come on if I tapped the outside of the unit. Once it warmed up it would work fine. Sometimes it would take one tap to get it to come on and run properly, sometimes it would take 2 or 3 taps before it would stay on. (I could always get it on by tapping, it just took more than once before it would stay on.)

I called one technician and he come out and told me it was the inducer motor and it would cost about $300. But he couldn't explain that would cause the symptoms I was experiencing.

So I called a second company and the guy from that company said it was the control board and would cost ~$900. But he kept pressuring me to buy a new HVAC unit, which I cannot afford, and continued to pressure me even after I said I couldn't afford a new unit. He also could not explain why a bad control board would cause the symptoms.

So I am confused. I could call out a 3rd company but I don't really want to spend another $85 to have someone come out and tell me something totally different. So I am looking to narrow down the problem so I have a better idea what to do and don't feel like I am being ripped off. My unit is a Day & Night by Carrier and is probably about 20 years old.

Thanks for any help you can give.

My heater won't come on by itself when its cold outside. It would work fine when is was sunny or above 50 degrees. I could get it to come on if I tapped the outside of the unit. Once it warmed up it would work fine. Sometimes it would take one tap to get it to come on and run properly, sometimes it would take 2 or 3 taps before it would stay on. (I could always get it on by tapping, it just took more than once before it would stay on.)

I called one technician and he come out and told me it was the inducer motor and it would cost about $300. But he couldn't explain that would cause the symptoms I was experiencing.

So I called a second company and the guy from that company said it was the control board and would cost ~$900. But he kept pressuring me to buy a new HVAC unit, which I cannot afford, and continued to pressure me even after I said I couldn't afford a new unit. He also could not explain why a bad control board would cause the symptoms.

So I am confused. I could call out a 3rd company but I don't really want to spend another $85 to have someone come out and tell me something totally different. So I am looking to narrow down the problem so I have a better idea what to do and don't feel like I am being ripped off. My unit is a Day & Night by Carrier and is probably about 20 years old.

Thanks for any help you can give.


Keep tapping of call a HVAC company that really knows what they are doing. It is impossible to tell you what is wrong since we cannot tap it from here with our meters hooked up. Sometimes a intermittent problem can be hard to find even if you are working on the unit. I would suspect some loose wiring or a bad ground.

On a old day and night,bryant,carrier unit a 3 wire pilot would cause that problem. Just a thought for you.

They look like this

Another possibility - a pressure switch that is sticking in the closed position when the previous cycle ends. Tapping the unit may cause the switch to open and allow another cycle.