Anyone have any reason why a roof mounted A/C unit would draw more amps than normal? I have had it for over two years (its on the camper that I bought used, was built in 2009), and it worked great from my house when plugged into a 30amp outlet, and also worked great with my Yamaha EF3000SEB inverter generator. Lately, it has been popping the house circuit breaker, as well as just shutting off when camping on the genny. No other loads on those circuits. Thanks! I have background in EE and other engineering fields, I cleaned the filter, it blows fine, no air restriction. Maybe a start or run capacitor? It blows great cold air still (while it's on!)

Sounds like you have a new A/C in your future.

Check your run capacitor they reduce your running amps.

cougar28 wrote:Check your run capacitor they reduce your running amps.Do you happen to know if it's accessible from below, or above?

Replace the start and run caps - they are considered a wear item on AC's and should be replace periodically (this includes home central units). Yours are up top.

OK, I see will try this. Have to climb on top and take the top off, and that little door to change the RUN CAP... THANKS!https://www.youtube.com/watch?v=Ty_ou_TW5EMI have done this several times on my home A/c units, mainly for the fan start cap...

Air Conditioner in toy hauler keeps drawing more amps

azdryheat
Explorer
Sep 04, 2019
Sounds like you have a new A/C in your future.
cougar28
Explorer
Sep 04, 2019
Check your run capacitor they reduce your running amps.
stacaz822
Explorer
Sep 04, 2019
cougar28 wrote:
Check your run capacitor they reduce your running amps.

Do you happen to know if it's accessible from below, or above?
ScottG
Nomad
Sep 04, 2019
Replace the start and run caps - they are considered a wear item on AC's and should be replace periodically (this includes home central units).
Yours are up top.
stacaz822
Explorer
Sep 04, 2019
OK, I see will try this. Have to climb on top and take the top off, and that little door to change the RUN CAP... THANKS!

https://www.youtube.com/watch?v=Ty_ou_TW5EM

I have done this several times on my home A/c units, mainly for the fan start cap...
Wild_Bill_888
Explorer
Sep 04, 2019
The filter protects the cooling heat exchanger from dirt dust pollen etc., but there is an outside air exchanger that dumps the heat, that is less well protected. As air flow is restricted, temperature and pressure increases loading the compressor more.

The most effective cleaning is with a medium velocity flow of water in the reverse direction of air flow. A high velocity flow will bend the fins over and plug the core.
SidecarFlip
Explorer III
Sep 04, 2019
Just BEFORE you stick your fingers in there... short across the can lugs to be sure the can is totally discharged.... But then I assume you already know that..

They don't all have dropping resistors.
stacaz822
Explorer
Sep 04, 2019
SidecarFlip wrote:
Just BEFORE you stick your fingers in there... short across the can lugs to be sure the can is totally discharged.... But then I assume you already know that..

They don't all have dropping resistors.

Heehee, I learned that at 5 years old. I was born with a soldering iron in my hands! At four years old, I grabbed the hot end in my dad's garage, and after that, I was expert with it, lol. As an aerospace test engineer, I know about large CAPS storing HIGH voltage for minutes, or even hours!
Chris_Bryant
Explorer II
Sep 04, 2019
Clean the coils.
wa8yxm
Explorer III
Sep 04, 2019
Two reasons. Most common. Condenser needs cleaning
Least common Compressor going going and soon to be gone.

If it is the condenser clogged. then it will start out normal and climb over a period of minutes.

If it's the compressor it normally starts high