My Trane AHU/CU cools great except that twice in the last 2 weeks the circuit breaker has tripped. Both times I have noticed it has got hotter in the house, I go out in the garage and the AHU Blower is blowing but the CU is not running. I check the panel and the circuit breaker is tripped. I reset it and the CU comes on and it cools great.:confused:

Oh how I hate intermittant problems:

Troubleshooting might involve:
1. Check operating pressures (service call)
2. Insulation test of compressor (service call)

So likely problems might be compressor breaking down and/or junk in the refrigerent lines.

An unlikely issue is that the system was moved from off to on without waiting and the thermostat/unit doesn't have an anti-short cycle delay.

It's hard to pop that breaker.

It is also possible that the circuit breaker is weak and tripping due to that issue or the wires at the breaker are loose and overheating the breaker .

Lots of queations I would need answered. New home with up to date wiring? Is your breaker big enough for the condensers amp draw? Does your conderser. Or thermostat have a time delay for restart? Is your condenser clean. If you have an old mercury thermostat, that is most likely your problem. Especially if you condenser is older than your thermostat. I would try a new thermostat if this is the case.

Home is 4 years old... I checked the wires to the breaker yesterday... they were tight... AC was running great... But the breaker was warm, not hot when I checked it and the AC had been running