I have a 2002 U320 - My front and rear A/C both work fine and the fans cycle on/off as would be expected. On occasion when the rear A/C turns off it will trip the shore 50 Amp Breaker.
I have a surge protector from the breaker to my rig. Is there something I can put in line to protect the shore breaker from tripping.
Any suggestions on what my be causing the power surge when the unit shuts down? This happens about 40% of the time. If I turn off the unit with the thermostat prior to it shutting off on its own the breaker does not trip.
Wow, that's a new one-- tripping a breaker when going from load to no load.
Has this happened on different 50 amp connections?
I would pull the cover off and check the connections where the coach wire connects to the AC wiring. Also check the circuit board to see if something does not look right on it. Such as burn marks, capacitors that have split or swelled out. Check also the run and start capacitor to see if split or swelled.
I am going to say there is problem with the control circuit board. Reason to say this is that is the common dominator between unit shutting off on it's own and being shut off by thermostat
"If I turn off the unit with the thermostat prior to it shutting off on its own the breaker does not trip."
Wonder what would be the difference in manually turning it off to the set temperature achieved turning it off.
I don't know why it is happening but when you turn the thermostat off the compressor shuts off before the fans do. When the air shuts off on its own they both shut down together.
Likely campground pedestal 50-amp breaker is the problem. Nothing you can do, except ask for the breaker to be changed.
Yup, that is why I asked if this was happening at more than one CG/pedestal.
Are you certain the rear AC shutting off trips the circuit breaker or is the Breaker tripping and thus shutting off the AC simultaneously?
Just a thought.
It just started last week and have been at the same location... will move to a new lot and check next week.
Matt Brown
2002 40' U320
Definitely the unit shuts off and the breaker trips... I have been testing it the last few days.
Matt Brown
2002 40' U320
When this happens does one or the other breaker feel warm or hot to touch it...this might indicate a failing breaker. Each A/C unit is on its own leg of the 240V pedestal, L1 and L2. If the breaker the rear A/C draws through is failing, it might only trip when hot, maybe explaining why it doesn't trip every time - and the front A/C runs fine on the other leg through it's own breaker. The L1 and L2 breakers are tied together so when one trips they both trip.
Also, inductive loads like the A/C compressor will create a voltage spike when power is disconnected. This will not usually trip a breaker unless it is weak and failing.
Thanks... I'll check it out.