If your air handler is making odd noises and it causes your circuit breaker to flip off, the problem could be a bad transformer. The transformer is responsible for stepping down power when necessary. One job it has is to reduce power from the thermostat to the contactor in the condenser.
If the transformer is bad, your condenser won't be able to fire up and run because the contractor doesn't get power from the transformer. Here's how an air conditioning repair technician might fix a problem with a bad transformer in your HVAC.
1. Test The Old Transformer
The technician can verify the transformer is bad by using a multimeter to test it. If it's bad, the transformer needs to be replaced. A transformer is usually in the air handler part of your HVAC near the control board for your AC. The first step in taking out the old transformer is to turn off the power and then disconnect all the wires that attach to it and then unscrew the ground wire. After that, the screws to the mounting plate are removed and the old transformer is pulled out.
The air conditioning repair technician has to choose the appropriate replacement part and then place it on the air handler frame and secure it with screws. It's important to screw the ground wire back on and to attach the other wires to the right terminals.
2. Check for the Cause of Failure
A transformer often blows because of an electrical problem with the AC. This could be due to a power surge in your electrical system or shorted wiring. The air conditioning repair technician may need to check the wiring and other parts for shorts by using a multimeter to find the part that caused the transformer to fail. A likely suspect is a contactor in the condenser outside. When it fails, the transformer might fail too. Once the culprit behind the problem is found and replaced with new parts, your AC should run normally again.
One thing to keep in mind is that a bad transformer will trip the circuit every time you turn the breaker back on. So, rather than turning the breaker on multiple times, leave the breaker off and call an air conditioning repair service and explain your problem. Trying to force a breaker to stay on could result in a fire or damage to the AC equipment. A breaker is a safety device, so when a breaker flips off, it's time to get help to figure out what is wrong with your HVAC system.