Air Conditioning - air handler won't turn off

I understand that I should be happier to run an air handler w/o a compressor than the reverse, however my air handler has been running constantly since startup this season. Even if I entirely remove the thermostat from all its (5) wires, the air handler keeps running. Any suggestions on what this could be?

Take and hit the side of the air handler hard with your hand. See if that dont work. lots of time the blower relay sticks on. If not check the G wire for a short back to the blower. You have already checked the tstat, By taken the wires off it.

I have tried hitting the unit about as hard as I can with a bare hand, with no luck. I also lifted the G wire from the terminal at the air handler and the unit still doesn't stop running. Any other ideas?

Have you tried just unplugging the unit from the receptacle and plugging it back in? Maybe this would reset it.......

Yes, I turned off the circuit breaker for over night, no luck. Thanks. What else could be causing this?

Your fan relay has failed closed. This is not a 1950's tv and whacking it isn't going to do jack.

You've disconnected the tstat which took power off of the fan relay. Since the fan kept running the relay is of course bad.

But, always is at least one but, is this a straight a/c or heat pump? Is it a furnace? Make model? Different ways to operate the fan on a furnace verses a/c, heat pump. Even so, the fan relay, which ever type is stuck closed.

Chris

Thanks, Chris. It is a Trane air handler, straight AC, not heat pump, and no furnace. I'll get the make / model number if it helps.

thanks again,

I can't get manuals from trane.

You need to call a tech and have the relay checked and fixed.

Let us know what happens.

Chris