Dometic AC unit won’t turn on

[DeanAir]

I have a 2015 23FB International, and the female plug on the circuit board disconnected from the board. I replaced the thermostat and plugged it into the phone-type cord. The thermostat does not give an E1 code on Zone 1, so it appears to be working fine.

I don’t have a 240v plug where my AS is stored. So, I connected power only to my truck, leaving the truck running. The Dometic AC unit will not kick in, not even the fan by itself. Does the AS need 240v land power for the unit to run? The breaker is not tripped.

[azflycaster]

Air Conditioning units require 120 volts of AC shore power.

[BayouBiker]

The AC controller uses 12V power but the Fan and compressor requires 120VAC shore power. Sounds like you have 2 ACs and 50A service. The 50A service is indeed 240 and a neutral, but the Airstream power center does not use the 240V. Instead it uses a hot and the neutral so 120V and it is split into two services so you have 100 Amps of 120V total capacity.

Because of this,you will want to be sure if you run into 30Amp service and use an adapter, you want to be sure the service is 120V 30A not 240V 30A. Household dryers use 240V 30A. Campgrounds are use 120V 30A.

[DeanAir]

Originally Posted by BayouBiker

The AC controller uses 12V power but the Fan and compressor requires 120VAC shore power. Sounds like you have 2 ACs and 50A service. The 50A service is indeed 240 and a neutral, but the Airstream power center does not use the 240V. Instead it uses a hot and the neutral so 120V and it is split into two services so you have 100 Amps of 120V total capacity.

Because of this,you will want to be sure if you run into 30Amp service and use an adapter, you want to be sure the service is 120V 30A not 240V 30A. Household dryers use 240V 30A. Campgrounds are use 120V 30A.

Thanks. There is one AC unit.

[BayouBiker]

Ah, okay the same caution applies. Be sure the 30A service is wired for 120V (one hot, one neutral and one ground). To test the AC you can get a 15/20A to 30A RV adapter. With everything else off especially the water heater, 15A 80% of the time will start and run the AC. It should only draw 13Amps running, 17-18 amps starting.

[PaulnGina]

It sounds lke you are extremely fortunate that there was NOT a 220 connection available where you store your AS, or the power system and who knows what else might be fried by now.


Please be aware that your Airstream needs 120V input.

[DeanAir]

Well, I have obviously used the plug over the years at campgrounds, with the 30-amp circuit. It looks different from a typical 120v plug. Regardless, will the AC unit run, even just the fan, with power slowly from the tow vehicle? Or, does it have to be plugged into shore power?

[DeanAir]

I just found in the manual that the unit likely will not run without at least 105v. I assume that power from the tow vehicle is nowhere near that. Correct?

[PaulnGina]

You will need shore power.

[PaulnGina]

Originally Posted by DeanAir

I just found in the manual that the unit likely will not run without at least 105v. I assume that power from the tow vehicle is nowhere near that. Correct?

Your tow vehicle will only provide 12VDC through the trailer connector.

[DeanAir]

Thanks! Can I use an adapter from a typical three-prong grounded plug to that used on the AS, and plug the three-prong into my truck since there is no power at the storage site?

[PaulnGina]

Originally Posted by DeanAir

Thanks! Can I use an adapter from a typical three-prong grounded plug to that used on the AS, and plug the three-prong into my truck since there is no power at the storage site?

You have AC power available from your truck?? I have seen that on newer vehicles (please know that my tow vehicle is a 1995 F250. nothing that fancy on my truck... ), but that won't provide much amperage.... those connections are for low-power needs like charging a phone.

[DeanAir]

Yeah. It’s awesome. Real-live plugs.

[BayouBiker]

I'm guessing the inverter in your truck is pretty small, probably less than 200 watts. You'd need a 2200 watt inverter to run the AC.

[DeanAir]

Thanks again for all of your help.

[rmkrum]

Toyota Tacoma has a single standard 120 volt AC plug in the bed. It’s only good for 200 watts while driving, 400 when in park. It’s not going to even start an air conditioner blower...

I use mine to run a small battery charger for the generator starting battery on the road. It’s kinda wimpy as far as most inverters go. Tundra doesn’t have one.