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Topic: #1 AC causing breaker to pop (Read 567 times) previous topic - next topic

#1 AC causing breaker to pop

Things were working fine, the firs t few times we needed the ac. But when we came out of Vegas, we stopped for lunch and utilized the genny.  Ac worked fine. But that night we discovered that it had popped the breaker. Before we shut off the genny,  I  made sure that the ac had cycled off,then shut it off.  This has occurred randomly for the rest off the trip. I always make sure to not stop the ac in mid cycle prior to shutting down for travel. We don't unplug the shore power till the ac's have cycled off and the switch has been moved to off.  Yet the #1 ac will pop the breaker.  I have never had this problem in my other coaches.  Any suggestions? 
Thanks in advance. Ps. Prior to this trip, coach had been seen at FT of Tx where we purchased her.
Lynn and Linda Day and Harry the pug
RIP: Tank 01-2008 to 03-2020
2012 Nimbus 42' build 6555
ISX12-500hp
2015 Jeep Grand Cherokee
MC# 17723

Re: #1 AC causing breaker to pop

Reply #1 –
Does it appear to only happen during a driving session?  If so, and the breakers are on the foot of the bed, it might just be a tired breaker that trips due to heat and/or vibration, especially if it's towards the bottom of the breaker panel (closer to the engine).  We have had to replace 3 or 4 of them over the years, starting with the bottom ones and working up.  In an '03 they're a common GE breaker from Lowes.  Not sure about a 2012.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: #1 AC causing breaker to pop

Reply #2 –
The breakers are suspect. We have had to replace them as well.  Get a spare while you are at it.  If you change it yourself be sure the land line is not plugged in and the inverter is off.  And then double check.  Not hard to do at all.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: #1 AC causing breaker to pop

Reply #3 –
I have replaced my #1 breaker twice. Last trip it worked fine on shore power but on the generator it kept popping the breaker.

Anyone know why only the front AC does this and not the other ones?
'07 Phenix Double slide, Bunk beds, 42'
'14 Wrangler Unlimited Rubicon

Re: #1 AC causing breaker to pop

Reply #4 –
While checking breaker make sure connection is tight. Loose connection will cause breaker to trip
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: #1 AC causing breaker to pop

Reply #5 –
Hi Darrell,

Possibly you have a weak circuit breaker if it shut off often or you have low voltage. Though this is not a great test, does it feel soft as you switch it on and off?
Jim Frerichs
2002 U320 42'

Re: #1 AC causing breaker to pop

Reply #6 –
Quote from: Darrell LeBeau –
I have replaced my #1 breaker twice. Last trip it worked fine on shore power but on the generator it kept popping the breaker.

Anyone know why only the front AC does this and not the other ones?
The front AC has the longest wire run back to the breaker box. The will cause a little more voltage drop and a little longer surge to get the compressor started. When on the generator, try always starting the front AC first, when generator voltage will be highest without any other loads. The highest surge is at turn on, starting both the fan and compressor. Once on, the fan is running, and just the compressor cycles.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: #1 AC causing breaker to pop

Reply #7 –
Probably a long shot, but if the capacitor(s) are bad, the start up load will be increased quite a bit.

Something that is not too difficult to check.  Remove the roof A/C cover and then (yes, with power OFF) the cover for the electrical compartment.

Check capacitors for discoloration or leakage.  Check electrically ONLY if you are safe and familiar with capacitors-- they store quite a jolt.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: #1 AC causing breaker to pop

Reply #8 –
Quote from: Jim Frerichs –
Hi Darrell,

Possibly you have a weak circuit breaker if it shut off often or you have low voltage. Though this is not a great test, does it feel soft as you switch it on and off?

Does not feel soft.
'07 Phenix Double slide, Bunk beds, 42'
'14 Wrangler Unlimited Rubicon

Re: #1 AC causing breaker to pop

Reply #9 –
Quote from: prfleming –
The front AC has the longest wire run back to the breaker box. The will cause a little more voltage drop and a little longer surge to get the compressor started. When on the generator, try always starting the front AC first, when generator voltage will be highest without any other loads. The highest surge is at turn on, starting both the fan and compressor. Once on, the fan is running, and just the compressor cycles.


I will try that sequence. Still confused on why it does not trip on shore power.
'07 Phenix Double slide, Bunk beds, 42'
'14 Wrangler Unlimited Rubicon

Re: #1 AC causing breaker to pop

Reply #10 –
Quote from: wolfe10 –
Probably a long shot, but if the capacitor(s) are bad, the start up load will be increased quite a bit.

Something that is not too difficult to check.  Remove the roof A/C cover and then (yes, with power OFF) the cover for the electrical compartment.

Check capacitors for discoloration or leakage.  Check electrically ONLY if you are safe and familiar with capacitors-- they store quite a jolt.


Good thing to check, Thanks
'07 Phenix Double slide, Bunk beds, 42'
'14 Wrangler Unlimited Rubicon

Re: #1 AC causing breaker to pop

Reply #11 –
Check the connection where the Airconditioner and coach wiring come together. The wire nuts on mine were melted. But it never tripped the breaker!
John Duld
1995 U320C SE 40'

Re: #1 AC causing breaker to pop

Reply #12 –
Only on the generator?
It might be worth checking the cycle output (60 cycles under some load) of your generator.
John Duld
1995 U320C SE 40'