what happens if?
- Thread starter tjvpga
- Start date
elkhartjim
Senior Member
Re: what happens if?
Do you have 30 amp service available? If so, cool away. Do you plug in at cg's to run your ac?
Do you have 30 amp service available? If so, cool away. Do you plug in at cg's to run your ac?
Re: what happens if?
I ran my 30 amp trailer A/C from a 15 amp household outlet. Not a problem, unless you also try to use the microwave or some other big draw. Most A/C will have a large startup current, over 20 amps, but it is too transitory to flip most breakers. Then they settle down to 10 amps or so, which is fine on a 15 amp circuit (assuming nothing else in the house using it).
If you want to cut down the startup surge, an 'easy start' kit can be installed in the A/C. I never had a problem with my 15 amp outlet, but the A/C would sometimes kill my 3000 watt honda generator until I installed an 'easy start' kit. It is a big capacitor and a relay, which gives an extra 'push' when starting the A/C to overcome a compressor which has not been used in a while.
I ran my 30 amp trailer A/C from a 15 amp household outlet. Not a problem, unless you also try to use the microwave or some other big draw. Most A/C will have a large startup current, over 20 amps, but it is too transitory to flip most breakers. Then they settle down to 10 amps or so, which is fine on a 15 amp circuit (assuming nothing else in the house using it).
If you want to cut down the startup surge, an 'easy start' kit can be installed in the A/C. I never had a problem with my 15 amp outlet, but the A/C would sometimes kill my 3000 watt honda generator until I installed an 'easy start' kit. It is a big capacitor and a relay, which gives an extra 'push' when starting the A/C to overcome a compressor which has not been used in a while.
Kirk
Senior Member
Re: what happens if?
The answer isn't nearly as simple as stated. There are several possible answers. Since your standard house type of outlet is a 15A, 120V supply, it will not supply any more than 15A and most RV air conditioners draw 13A if the power stays at 120V. Now the catch is that while the design voltage is 120V, in reality you will probably have very close to that at the outlet, you now have a heavy cord plugged into a minimal supply and if your house wiring is less than perfect the voltage will begin to droop from the load.
Now that isn't a big deal until the voltage drops below 108V but it is if that happens. Since your RV always has some loading from the 120V/12V converter, you will probably exceed the 15A limit as soon as you start the air conditioner and the circuit breaker will open in the house's distribution panel.
If for some reason the voltage does fall to 108V, the current now demanded by the motors inside of your air conditioner will rise to 14.5A and you will trip the circuit breaker for sure. If that breaker does not open the air conditioner will over heat in time and it could damage the motors inside.
The other factor is how large is the air conditioner that your RV has? If it is the most common, it will be 15,000 BTUs and draw about 13A but if your RV is small, it may have one of the smaller units that draw less. The more common other sizes are 13,500 & 11,000 BTUs. The smallest one draws around 8A under normal conditions, the middle one about 10A.
In short, as long as the voltage stays up in the 110V range or above and the house circuit breaker does not open, it will probably be fine. What I would do is to try it, but monitor the voltage inside of your RV when you first start to make sure that it does not sag.
The answer isn't nearly as simple as stated. There are several possible answers. Since your standard house type of outlet is a 15A, 120V supply, it will not supply any more than 15A and most RV air conditioners draw 13A if the power stays at 120V. Now the catch is that while the design voltage is 120V, in reality you will probably have very close to that at the outlet, you now have a heavy cord plugged into a minimal supply and if your house wiring is less than perfect the voltage will begin to droop from the load.
Now that isn't a big deal until the voltage drops below 108V but it is if that happens. Since your RV always has some loading from the 120V/12V converter, you will probably exceed the 15A limit as soon as you start the air conditioner and the circuit breaker will open in the house's distribution panel.
If for some reason the voltage does fall to 108V, the current now demanded by the motors inside of your air conditioner will rise to 14.5A and you will trip the circuit breaker for sure. If that breaker does not open the air conditioner will over heat in time and it could damage the motors inside.
The other factor is how large is the air conditioner that your RV has? If it is the most common, it will be 15,000 BTUs and draw about 13A but if your RV is small, it may have one of the smaller units that draw less. The more common other sizes are 13,500 & 11,000 BTUs. The smallest one draws around 8A under normal conditions, the middle one about 10A.
In short, as long as the voltage stays up in the 110V range or above and the house circuit breaker does not open, it will probably be fine. What I would do is to try it, but monitor the voltage inside of your RV when you first start to make sure that it does not sag.