Community Forums

Dixster · 06-17-2021, 04:55 PM

New problem - connected to 50 amp campground pedestal,
which show correct voltage for each leg (campground just
replaced each breaker for me).

Coach seems to be running on 30 amps through the electrical
management system and will only provide continues power to
the front ac. Second ac runs for just a few minuets and then
looses all power. All else in the coach seems to run ok.

Turn pedestal breakers off and back on, both ac's start, but second
will loose power after running a short time (5 to 10 minuets).
Act's just like a weak circuit breaker, but doesn't trip the breaker.

onebrit · 06-19-2021, 06:07 PM

Hi
I think a previous post mentioned you may be losing a leg on the post under load, I would try what he said first try another power source, if that doesn't solve your problem then you may have a problem at your transfer switch where power cord enters the coach. If you are comfortable with working on electrical systems and safe and have a volt meter you can check that at the terminals in the switch to see the voltage drop. It could even be a problem in the cord/plug assembly. But switching power source would eliminate or confirm that.
Good Luck be safe.
Onebrit

Dixster · 06-20-2021, 11:18 AM

Onebrit
Thanks for the reply - First I checked the 50 amp ATS lugs for being tight, which they where.

Next a voltage check on input and output (no load) all checked good, all legs. Next front and back AC now show power available. Started front AC OK. Tried rear AC, heard and thunk (unable to find where it cam from) and power went dead to rear AC display. Still show correct power to both output legs of the ATS

Turned circuit breaker (50 amp pedestal) off and back on. Now both AC's run as usual.

After running for some time the rear AC again stopped and lost power to the display after trying to start again.

Could it be I've got a 14 year old AC (back one) going south ?

Thanks again for your time and ideas.

twinboat · 06-20-2021, 01:30 PM

If you have a load sheading device showing 30 amps while on 50 amps, check for circuit breakers off in the main panel.

You may not be using them, but the load sheading device may be connected to them.

Dixster · 06-21-2021, 08:51 PM

Things have changed - now 50 amp is running correctly - except rear air (replaced in 2015) - shows power on thermostat, but when it's turned on I hear a click and the ac goes dead. After a short period the power reappears on the thermostat. Is there a resettable breaker in the AC ?

ktoutoor · 06-29-2021, 04:17 PM

I added this to my 38J great for trouble shooting amp loads by the leg

https://www.youtube.com/watch?v=nTkjfbqvvTE

jerichorick · 06-29-2021, 05:45 PM

Quote:

Originally Posted by Dixster

Things have changed - now 50 amp is running correctly - except rear air (replaced in 2015) - shows power on thermostat, but when it's turned on I hear a click and the ac goes dead. After a short period the power reappears on the thermostat. Is there a resettable breaker in the AC ?

I don't know what you mean by power to thermostat going off and on. Are you saying you are loosing a zone? You could have a bad relay in the controller in the A/C. Do the following:
Turn the breaker for the bad A/C unit off.
Remove the shroud
Remove the plenum cover on the front of the unit. There are several screws around the edge of it. Lift and pull.
The controller is the thing all the wires go to. Undo the left and right wingnuts from the mounting posts.
Pull the unit up and remove the 4 screws holding the cover on.
Under the cover is the control board and several relays. I have had problems with these relays and with burnt wires. If you need a relay let me know. I have several spares. I will give you what you need. I bought to many thinking I needed them. Wrong thought.

A new starting Cap might be in order also if the above is not the problem.
When you button it al back up make certain to get the freeze sensor back into the condenser coil securely.
Looking forward to hearing what the trouble fix is.
Rick

Knightly · 06-30-2021, 07:48 PM

I am not sure if this will help. About five years ago, I had similar problems with voltage issues and basement heat pump failure. It might be worth looking at the control board. It looked fine at first but when I turned it over, I did not need to look any further. The underside of the circuit board showed evidence of over heating, burnt wires, etc. Replaced with a new board and all was well.

twinboat · 06-30-2021, 09:11 PM

Quote:

Originally Posted by Dixster

Things have changed - now 50 amp is running correctly - except rear air (replaced in 2015) - shows power on thermostat, but when it's turned on I hear a click and the ac goes dead. After a short period the power reappears on the thermostat. Is there a resettable breaker in the AC ?

Many thermostats are powered with 12 volt power. If its going dark, it may be a 12 volt, auto reset, breaker issue.