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c177tx · 07-22-2015, 11:34 AM

I have been full timing in my 2008 Bambi for 6 years. Texas heat, 13.5 AC. On a 20 amp using an adapter, No problems.

Crabpot · 07-23-2015, 08:18 AM

Have been running my AC off a 20 amp circuit all summer with no problem. It is a dedicated circuit with only the AC and a other AS light running....

lewster · 07-23-2015, 10:07 AM

Quote:

Originally Posted by wxbuoy

Start up is where the damage to the A/C is going to occur. The sell what is called hard start capacitors to replace the one currently installed. Basically it is a larger voltage storage device so when the compressor kicks in it gets the initial load from it vice dropping the current and doing damage. It then " recharges" while running at normal wattage draw.

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If the engineers that design the electrical systems of these A/C units felt that they required capacitors of different ratings, they would have called for them in the original designs.

Using ANY electrical device that deviates from the original specifications in a rated (UL or CE) appliance is not only asking for future problems, but will also de-rate the unit. In a new unit, it will void the warranty and in an older unit, should use of said appliance be the cause of a fire, you can be sure that the insurance company's fire inspectors will be looking very closely for any modifications like this to the appliance.

I have been involved in more than one instance of this and in each case, the unauthorized modifications that the owner performed on an appliance that was determined to be the cause of damage to the RV totally absolved the insurance company of any payment requirement.

JUST USE THE PROPER SIZE CABLES AND OUTLETS!!!!!! It's really very simple.

HowieE · 07-23-2015, 11:24 AM

You have pretty much answered what you have to look after within the trailer. Now look at his house.

When we say NOTHING ELSE we mean nothing else on that circuit. No clock in the bathroom or light in some remote room. After the AC has run for an hour or so feel the wires as the enter the panel box. If one is warm you are running above the limit.

mandolindave · 07-23-2015, 11:48 AM

I read somewhere here that, if you going to use an AC with a 20 breaker, that you should turn it on full blast and leave it there, or turn it off.

You are not doing the unit any favors as the cycling off and ON is when the damage is done. Maybe leave a window open so the unit has to keep working. Maybe use open windows as a temp control if it gets a little to cold.

DISCLAIMER….I AM NOT AN ELECTRICIAN

HowieE · 07-23-2015, 01:09 PM

In general the starting function of any motor does more damage per unit time than running time. That is a fact but not one that should come into the consideration of running an AC unit, especially if you are going to run the unit at a 100% duty cycle by causing a fake load by leaving the windows open.

Most miss the fact that more than half of the function of an AC is to reduce the humidity level in a space. Leaving the windows open you will never achieve anything relating to comfort.

Smaller motors, the fan motor, that can be run at different speeds do this by putting a load resistor in series with the motor windings. That load resistor produces heat while slowing the fan motor. So under this consideration I would suggest running the fan at high speed, no useless heat, and let the AC cycle against the thermostat.

idroba · 07-24-2015, 01:23 AM

Quote:

Originally Posted by NevadaGeo

If your compressor stalls on start up, unplug it before you let the smoke out. If the compressor don't like the electricity you are feeding it, it'll stall and fume and smoke about it. It don't care what others here are saying about it. Mine, likes 30 amps to start. Won't start on 20 amp. Doesn't matter if it would "run" on 20 amp if it won't start.

Since the compressor is hermetically sealed with the motor totally inside the refrigeration shell it will not smoke. If it becomes overheated, the internal thermal cut off will open the circuit, and reset when it cools down. But no smoke.

J. Morgan · 07-26-2015, 04:58 PM

I bet near everyones RV air conditioner runs on a 20 amp circuit breaker.....

The breaker in the trailer is 99% going to be 20 amp.

AtomicNo13 · 07-26-2015, 05:05 PM

Ok that's all folks!
I have been waiting for someone to post that reply!

With that being said, can't argue with 20 amp breaker math!

Paulaale · 09-20-2015, 07:15 AM

Ok I ran mine with and extension cord to a household plug that had other items in it. And just like everyone stated it blew the breaker. My newly acquired trailer the fan did not come on. But I did hear the compressor could that mean my 1964 still has a good air-conditioner? Thinking about repairing instead of replacing any suggestions?

rgwatkin · 06-18-2021, 08:38 PM

So .. I am in Vegas today at 115F, AC Runs for 15 min then trips, then have to wait 15min for the 20a breaker to cool and so it goes on. Checked cleanliness of coils etc. Tightened all lugs/connections. At 115 I was sure tempted to put the ac wire on the 30amp main but better judgment prevailed. I measured voltage and it was within range. It started working at exterior temp of 105F.. so am I to think I just have 105F ac unit? Problem always is. You take in for service and conditions are never same elevation and/or temp. I just think it is under designed for the application.

HowieE · 06-19-2021, 03:46 PM

You should be able to run the AC on 20 amp as long as nothing else is turned on. The ref., the convertor, and any thing charging a device has to be off.
If that fails and the AC shuts off but the breaker remains on the AC has most likely tripped off on high head pressure due to the high ambient temperature. Doubt if you will be able to play water on the AC when it first starts but I have done that and got it over the hump with about 20 minutes of spraying the condenser coils.

In any case don't attempt to run the AC if the voltage is below 105 as you run the risk of killing the compressor.

Fungus · 06-19-2021, 07:40 PM

I run 15k AC on 20 amps at home. The AS breaker inside the trailer for the AC is 20 amps. Don’t use a wimpy extension cord. Don’t run anything else on the house circuit…it will trip. Don’t run the microwave or water heater in the AS.

rowiebowie · 06-19-2021, 08:15 PM

Quote:

Originally Posted by Fungus

I run 15k AC on 20 amps at home. The AS breaker inside the trailer for the AC is 20 amps. Don’t use a wimpy extension cord. Don’t run anything else on the house circuit…it will trip. Don’t run the microwave or water heater in the AS.

I second this^.

I run my 15K btu at home on 20A line with no problems. But, it is a new ac that uses about 11-12 amps (2 amps less than the old 13.5k model I replaced).

reputnam503 · 06-20-2021, 11:41 PM

You should add a soft start for your AC unit. It reduces startup amperage about 70%.

Also, on a real hot day it is harder to run an AC than on a normal day. The soft start will help a lot.

Google Easy Start 364 by Micro Air. This should be standard equipment on all air conditioners.

Fungus · 06-21-2021, 06:21 AM

I didn't need the Micro-Air EasyStart to run my 2017 15K unit on an empty 20 amp circuit.

But, I installed the EastStart this week so I could run the AC on a 2400-watt generator. Fairly easy installation. Took me longer to figure out how to get on/off the roof safely.

s1000pre · 06-21-2021, 07:04 AM

Quote:

Originally Posted by J. Morgan

I bet near everyones RV air conditioner runs on a 20 amp circuit breaker.....

The breaker in the trailer is 99% going to be 20 amp.

As most have already replied and as long as your extension cord can handle it, yes you can. My 2021 has a 20amp breaker for the AC, I use a 10AWG cord. Make sure everything else is turned off.