Luckily the utility had documented the voltages in April.
They just happened to return recently for another issue and measured the voltages again. This is how we became aware that there may be a problem. Today we isolated the motor that was causing the voltage imbalance. What seemed strange was that there were 2 identical compressor motors. One was running very hot. Hot enough to discolor the plastic label on the motor. The other motor was luke warm so you could put your hand on it. Right away we thought it must be the motor that is running hot. After shutting them down individually it turned out to be the cooler motor that was probably causing the problem. We were told the hotter motor was running within temperature specs.
Next steps:
Meg the motor, check the motor connections and the contactor contacts. Anyone want to throw in their 2 cents about motor megging?
