Power the AC with household circuit
My trailer's AC won't run unless it's plugged into an external 30 amp power source like full service campgrounds. At home I use an adapter to plug into my house's outdoor outlet, which will run every...
Forum Discussion
It's all about the voltage. (Cue Meghan Trainor...)
If you read the tech specs on your AC unit, you'll find it is supposed to have a 20 amp breaker and wire over 50' needs to be min. #10. For longer runs, even larger wire may be needed. The overall wire length includes all wire from the terminals at the AC unit to the breaker in the panel. The breaker only has to be large enough to allow an AC unit to start (within normal operating voltage specs) so a 15 amp breaker is okay if it doesn't trip. Also depends on other loads in an RV running at the same time.
Sometimes even the wire from your house panel out to the street can be a factor in voltage drop. That's why lights can in some cases flicker when a fridge compressor or washing machine motor starts up.
Besides the running current of an AC unit, it draws about 5-6 times the full load amps on the momentary startup which is around 60 +/- amps depending on unit BTU rating. That is why the wire over a certain length needs to have a current higher than the breaker or full load current draw of the AC unit. If wire size is too small, the voltage at the AC unit can drop very low.
Low voltage will damage AC units and should never be allowed to drop below 105 volts. The damage is cumulative and while it may *seem* like it's running fine, it can fail prematurely for no apparent reason. Too small wire size can cause large voltage drop on startup or running that damages the motor windings. AC units draw more current as voltage goes down, further exacerbating voltage drop.
Installing a permanent voltmeter inside an RV is always a good idea so you can monitor voltage wherever you happen to be. Voltage can also fluctuate widely over 24 hours depending on other nearby users.
Ensure cord plug blades are kept clean 'n shiny. The inside of receptacles and cord connectors can't be seen so if they look well used and abused, you may want to replace them.
If you read the tech specs on your AC unit, you'll find it is supposed to have a 20 amp breaker and wire over 50' needs to be min. #10. For longer runs, even larger wire may be needed. The overall wire length includes all wire from the terminals at the AC unit to the breaker in the panel. The breaker only has to be large enough to allow an AC unit to start (within normal operating voltage specs) so a 15 amp breaker is okay if it doesn't trip. Also depends on other loads in an RV running at the same time.
Sometimes even the wire from your house panel out to the street can be a factor in voltage drop. That's why lights can in some cases flicker when a fridge compressor or washing machine motor starts up.
Besides the running current of an AC unit, it draws about 5-6 times the full load amps on the momentary startup which is around 60 +/- amps depending on unit BTU rating. That is why the wire over a certain length needs to have a current higher than the breaker or full load current draw of the AC unit. If wire size is too small, the voltage at the AC unit can drop very low.
Low voltage will damage AC units and should never be allowed to drop below 105 volts. The damage is cumulative and while it may *seem* like it's running fine, it can fail prematurely for no apparent reason. Too small wire size can cause large voltage drop on startup or running that damages the motor windings. AC units draw more current as voltage goes down, further exacerbating voltage drop.
Installing a permanent voltmeter inside an RV is always a good idea so you can monitor voltage wherever you happen to be. Voltage can also fluctuate widely over 24 hours depending on other nearby users.
Ensure cord plug blades are kept clean 'n shiny. The inside of receptacles and cord connectors can't be seen so if they look well used and abused, you may want to replace them.
