Shore power
Can You Run two air conditioners on 30 amp RV Service?
Researched from published standards and manufacturer specifications. Updated .
Quick answer
Two 13,500 BTU rooftop units running together. The arithmetic on a pedestal is simple once you know what the service actually supplies, and that is where most of the confusion sits.
A 30 amp RV service is a single 120 volt leg at 30 amps, which is 3,600 watts. A 50 amp service is two separate 120 volt legs at 50 amps each, which is 12,000 watts. A 50 amp pedestal is therefore more than three times a 30 amp one, not 67 percent more. Work out your own combination on the shore power budget calculator.
Does two air conditioners fit on 30 amp service?
| Figure | Value | Notes |
|---|---|---|
| Service device | NEMA TT-30 | One 120V leg |
| Total available | 3,600 W | 30A at 120V |
| This load | 2,800 W | About 23.3 A at 120V |
| Headroom remaining | 800 W | Within the service |
Published standard Source: NEMA TT-30 device rating.
What else can you run alongside it?
With 800 watts left, this is what still fits.
| Appliance | Running watts | Fits in the headroom |
|---|---|---|
| RV air conditioner, 13,500 BTU | 1,400 W | No |
| RV air conditioner, 15,000 BTU | 1,700 W | No |
| Residential refrigerator | 150 W | Yes |
| 12V compressor refrigerator | 45 W | Yes |
| Microwave, 1000W output | 1,500 W | No |
| Electric kettle | 1,500 W | No |
| Coffee maker, drip | 900 W | No |
| Toaster | 1,200 W | No |
| Induction cooktop, single burner | 1,800 W | No |
| Space heater, low setting | 750 W | Yes |
| Space heater, high setting | 1,500 W | No |
| Hair dryer | 1,500 W | No |
Convention Source: Typical published draws. Read the data plate on your own appliances..
Would 50 amp service change the answer?
Yes. A 50 amp pedestal supplies 12,000 watts against 3,600 on 30 amp, which would leave about 9,200 watts of headroom rather than 800. That is the difference between running one air conditioner carefully and running two without thinking about it.
An adapter does not change any of this. A dogbone adapter changes the plug shape and nothing else. A 50 amp rig on a 30 amp pedestal has 30 amps total for the whole coach, and a 30 amp rig on a 50 amp pedestal still has 30 amps.
Camco PowerGrip Dogbone, 50A Male to 30A Female
$16.11A dogbone body puts the strain on the cable rather than on the pedestal receptacle. Note that this adapter does not increase available amperage.
Best for: A 30A rig at a 50A pedestal.
Check price on Amazon
ELEGRP 50A to 30A Dogbone Adapter
$19.99NEMA 14-50P to TT-30R, which is the exact pairing for plugging a 30A rig into a 50A pedestal.
Best for: A 30A rig in a 50A site.
Check price on AmazonHow do you stop tripping the pedestal?
Sequence the loads rather than adding capacity. Switch the water heater and the fridge to propane, which frees up over a kilowatt between them. Run the microwave or the kettle only while the air conditioner is between cycles. Fit a soft starter so the air conditioner startup surge stops tripping the breaker even when the running load fits comfortably.
A surge protector with an electrical management system also guards the other direction. Parks with sagging voltage under summer load damage compressors quietly, and an EMS disconnects before that happens.
Progressive Industries EMS-PT30X, 30A
$135.89An EMS disconnects on low voltage, high voltage, open ground and reverse polarity. A plain surge protector only handles a spike.
Best for: Anyone plugging into parks they have not vetted.
Check price on Amazon
Power Watchdog PWD30 Bluetooth, 30A
$139.99Reports actual pedestal voltage and current to a phone, which is how you catch a sagging pedestal before it damages a compressor.
Best for: Watching pedestal quality over a long stay.
Check price on Amazon30 amp shore power protection
Progressive Industries EMS-PT30X, 30A
$135.89An EMS disconnects on low voltage, high voltage, open ground and reverse polarity. A plain surge protector only handles a spike.
Best for: Anyone plugging into parks they have not vetted.
Check price on Amazon Power Watchdog PWD30 Bluetooth, 30A
$139.99Reports actual pedestal voltage and current to a phone, which is how you catch a sagging pedestal before it damages a compressor.
Best for: Watching pedestal quality over a long stay.
Check price on Amazon
Power Watchdog PWD30EPO, 30A, IP65
$305.31An IP65 body, which matters because a portable unit sits on the ground at the pedestal in the weather.
Best for: A portable unit left outdoors.
Check price on AmazonFrequently asked questions
- Can I run two air conditioners on 30 amp RV service?
- Yes. It draws about 2,800 watts and 30 amp service supplies 3,600 watts, leaving roughly 800 watts for everything else. Watch the startup surge rather than the running figure, because a compressor starting can briefly draw twice its running load and that is what trips a breaker.
- How many watts is 30 amp RV service?
- 3,600 watts. A 30 amp RV service is a single 120 volt leg at 30 amps, which is 3,600 watts. It is not 240 volts, despite the large plug.
- Does a 50 to 30 amp adapter give me more power?
- No. An adapter changes the plug configuration and nothing else. Plugging a 30 amp rig into a 50 amp pedestal still limits you to 30 amps, because the rig's own inlet, cord and main breaker are all 30 amp rated. Going the other way, a 50 amp rig on a 30 amp pedestal has 30 amps total for the entire coach across both legs.
- Why does my breaker trip even though the math says it fits?
- Startup surge. A motor draws far more current for the first fraction of a second than it does running, and an air conditioner compressor can briefly pull more than twice its running load. A pedestal breaker sees that spike. A soft starter reduces the inrush substantially and is usually cheaper than any other fix.
Shore power safety. An adapter never increases the amperage available to you. Test a pedestal before connecting, or fit a surge protector with an electrical management system that checks for open ground, reverse polarity and out of range voltage and disconnects on its own. Low voltage damages motors and compressors just as surely as a surge does.