Hello, I'm working on my neighbors Cruisair
SMXII AC/Heat unit. The boat
is plugged up at the marina. When the associated breaker on the boat
is switched on the marina breaker for that switch immediately trips, but the boat breaker does NOT trip. No power on the control panel
, no noise
, nothing. Just immediately trips the breaker. This started occurring after rolling out the new gfci installation
at the marina. No surprise there. The panel within the boat has several other breakers/devices that work
fine with tripping the marina breaker. So the boat panel seems to be properly grounded.
Here's what I've done so far:
1. Switched the circuit to another breaker, same result. Breaker presumably good.
2. Disconnected the circuit power at the unit to test the wiring
for shorts. Neither circuit breaker tripped. Wires all ohmed out at less than 5 ohms. Wires presumably good.
3. Disconnected the water pump
from the circuit. Marina breaker tripped, boat did not. Pump
4. Checked start and run capacitiors with meter and they both tested OK.
5. Disconnected the fan wire from the logic/power controller. Breaker still tripped.
6. Disconnected the compressor
from the circuit. Breaker still tripped.
7. Found a ground going from the motor
to the unit case. Disconnected it from the unit case and jumped it straight to the ground lug for the unit. Breaker still tripped.
8. Checked the main connector from the logic/power controller and noticed the fan control terminal wasn't pushed all the way into the connector. Fixed that. Breaker still tripped.
9. Disconnected the logic/power controller from the unit and the breaker DID NOT TRIP.
I am assuming that the power logic controller (smxII) is defective, but I've also read that the smxII will trip the breaker if the supply voltage is too low. Not sure how true that is. However i did check the input voltage and it's reading at 120vac.
Has anyone else seen this? Do the controllers fail in this fashion? Any experience or advice would be appreciated. Thanks!