Change the fan relay switch on the air conditioners air handler system?

Question

I turned my thermostat completely off and the fan in my air handler system in my attic continues to run. The only way it will turn off is if I cut the main at the breaker box. I was told it was the fan relay switch. Is this right and can I change it myself ?

Answer 1

The fan in your attic may be controlled by a type of switch called a humidistat. The switch senses the amount of humidity in the air and turns the fan on when the humidity reaches a certain amount. Its possible that the fan and ac are on the same circuit, but the fan may not be controlled by the thermostat.

Otherwise, if you are sure that the problem is the fan relay, you should be able to replace it yourself. Turn the power off at the main breaker so you can remove the fan relay. Take the relay to a supplier to make sure you get an exact replacement, and install the new one. I would think you could get a replacement from a heating and air conditioning supply store.