Air Handler Fan Wont Shut Off

Posted on Feb 6, 2014

A Goodman Janitrol 2. 5 ton Standard Air Handler model #ARUF030-00A-1. After troubleshooting, I discovered that the only way to shut the fan off is by turning off the breaker or disconnecting the black wire that leads from the fan to the circuit board. There are 5 wires connected to the fan. 2 (brown) go to the capacitor, 2 (red, black) to the circuit board and 1 (purple) to the contractor relay. After extensive trouble shooting I

Air Handler Fan Wont Shut Off
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narrowed the problem to be with the black wire that leads from the fan to the circuit board because disconnecting that wire is the only way besides shutting off the breaker that stops the fan from running. With the black wire connected and all the other wires disconnected the fan continues to run but with the black wire disconnected and all the other wires connected the fan does not run. Am I correct with my assumption and if so does it mean that the whole board will have to be replaced Yeah, looks like you would have to replace the board. Or if you prefer, you could install a relay and make the fan go on and off with the thermostat. Boards usually cost 200 to 300 dollars, while a relay will cost you about 20 dollars. You are sure that the t stat is set to fan auto Did you recently replace the fan A fan continuously running on air handlers is usually a sequencer problem. (Unless it is a Goodman with the sequencer style fan control instead of the circuit board) A digital "meat" thermometer can help determine if we have a heat rise across the air handler with the thermostat turned off. (Pros would usually measure amperage) Houston204, before I posted to this site, I disconnected the the contractor relay which I just learned is called the transformer because I thought it was the problem and I reconnected the wires but I am not sure if I reconnected correctly because now the thermostat won`t turn on at the wall location. It...

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