We just bought a new-to-us Funfinder Travel Trailer and need to check out the A/C. Unfortunately I don't have a 30amp receptacle at the house. Does anyone know how long I can run the A/C on 15/20 amp circuit?

If you make sure that nothing else is being used (converter, etc) on your 110VAC circuit, the 20A circuit should work fine.....depending on the size of your A/C unit.Get a multi-meter, and when you plug in the camper (with the adapter), check the voltage at one of the outlets in the RV.....then start the A/C, and check the voltage again....if it drops below 105 VAC, you probably don't want to run the A/C very long.....but you should still be OK if it's above that.Good luck, and enjoy your new RV:)

What is important isn't time, it is the VOLTAGE inside the RV when the A/C is turned on.According to ANSI C84.1-1995 (R2001) any voltage below 110 volts for long term, or 106 volts for short term (seconds), may very well damage things in your RV (most commonly air conditioners, but anything could be damaged).So unless you like to live dangerously, get a voltmeter. If you are plugging into a house, you could still have a problem. The electric company could be providing a low voltage, you could have too much drop within the house wiring, you could have overloaded circuits, etc, etc, etc.

Is the circuit 15 amp or 20 amp? if 20 amp I would think you could start it up to see if it cools, then immediately shut er down.bumpy

With a reasonable extension cord you can run it forever on a 20 amp circuit - that's probably what it is on inside the trailer. I ran mine for days on a 15 amp circuit at home, dedicated with a 10 gauge cord but it would blow the breaker on start-up with another 15 amp circuit. Advice about voltage is dead on.Brian

Let me list what I do here to power up my two 30AMP trailers in my backyard. Maybe it will trigger what you may want to do on your end connecting up to the house/garage. I run two 120VAC drop cords from my garage to power up my 30Amp fifth wheel and 30Amp OFF-ROAD POPUP trailer when parked here at the house. One receptacle in the garage is a stand alone receptacle that was installed to run an air compressor at one time and this is the only thing on its circuit. I use this to feed my fifth wheel. My OFF-ROAD POPUP uses a 120VAC receptacle that located near the garage door and is on a different circuit breaker then the one I am using for the fifth wheel trailer.Before hooking up to the Garage 120VAC receptacle I would use a circuit tester from LOWES -WALMART that looks like thisDo not use the garage 120VAC receptacle if it does not check out "CORRECT" by the correct position of the tester lights...What I do is use two 10-GAUGE (10-3) HD Contractor type 50-foot that run out towards both trailers. I have used a 12-gauge (12-3) long extension cord with out any issues but would never use the 14-16 gauge "RED ORANGE" smaller size extension cords you find at LOWES-WALMART. They are just too small to handle the trailers.Out in the middle of the yard I use a RV30A-15A DOGBONE STYLE long adapter plugged into the 50-foot extension cords. These come from WALMART and look similar to this...I could never use the small round black type RV30A-15A adapters as they always tend to get hot me when used just a short time... What you don't want to happen is for the adapters to heat up your shore power cable which might end up looking like this and will need to be replaced.Now all I do is plug the 30AMP trailer SHORE POWER CABLE into this RV30A-15A long adapter laying in the middle of the yard.To insure the 120VAC power source is safe to use I will use one of these RV PLUG IN 120VAC AC voltmeters (AMAZON) plugged into a receptacle inside the trailer that is in a good view spot so you can glance at it when you need to. This will check the 120VAC level coming from the house. The part I like about this meter is it has a safe zone "GREEN" printed on the face and if the AC voltage is within this safe limit then is ok to use the power - even for one roof mounted air conditioner unit. I will turn a few thing on inside the trailer for 10-minutes or so and then back outside and check all of the connection points to see they are not getting warm to touch. This includes the garage 120VAC receptacle.This is pretty much what we do here for our two trailer that is hooked up to the 15AMP service from the garage.We can run just about everything inside the trailer we want to run but have to watch sometimes what is on at the same time. i.e. we can never run the air conditioner and the high wattage microwave at the same time otherwise it will trip the breaker in the garage.We sleep in both the trailers all the time when sitting in camp back yard and of course this is where I get to do all my mods and fix up things for the every changing OFF-ROAD POPUP configurations for my emergency radio operations I am connected with. Its a great get away just sleeping over in the back yard sometimes. Wifes gets to use the fridge to supplement her kitchen fridge. Good spot for my beers too...ALot of folks will warn you about about all kinds things that might happen when only connected to a 15/20AMP service but if you follow some good guidelines like I have listed here you should be ok. Has worked good for me over the past few years.We use the extension cord and RV30A-15A long adapter when on the road alot. You never know when we may need some power sometimes. Works great when visiting family - I just hookup outside their house and we sleep in the trailer.Hope this helpsfood for thoughtRoy Ken

20 amp Circuit & A/C? | Good Sam Community

12 Replies

Chuck_Gail
Explorer
Jul 19, 2013
What is important isn't time, it is the VOLTAGE inside the RV when the A/C is turned on.

According to ANSI C84.1-1995 (R2001) any voltage below 110 volts for long term, or 106 volts for short term (seconds), may very well damage things in your RV (most commonly air conditioners, but anything could be damaged).

So unless you like to live dangerously, get a voltmeter. If you are plugging into a house, you could still have a problem. The electric company could be providing a low voltage, you could have too much drop within the house wiring, you could have overloaded circuits, etc, etc, etc.
PapPappy
Explorer
Jul 19, 2013
If you make sure that nothing else is being used (converter, etc) on your 110VAC circuit, the 20A circuit should work fine.....depending on the size of your A/C unit.

Get a multi-meter, and when you plug in the camper (with the adapter), check the voltage at one of the outlets in the RV.....then start the A/C, and check the voltage again....if it drops below 105 VAC, you probably don't want to run the A/C very long.....but you should still be OK if it's above that.

Good luck, and enjoy your new RV:)

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20 amp Circuit & A/C?

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