12v power for 2nd AC

[dbareford]

I am working on a second AC install project. I am putting in my bedroom an Atwood Aircommand 15000 BTU (AC-1511W) that is the same as what I currently have installed in the front. Reading the owners manual it says it needs a 12v connection in addition to the 120v connection. Is that necessary? What's that for? Here is a excerpt from the manual.

[A32Deuce]

Thermostat maybe?

[Bama Rambler]

Yeah, the 12 volts is for the thermostat.

If it's a big pain to get 12 volts to the ceiling you can cheat and use a small 120VAC to 12VDC transformer like a wall wart and power it from the 120 volt power. Of course, if the unit is prewired for a second A/C then the 12 volt wiring is probably already there. If it's not then you're likely picking up the 120 volt power from the power panel. Just run a pair of 12 volt wires along with it from the DC side of the panel.

[dbareford]

Thanks for the info. I am pre-wired for a fan back there, so I have 12v wires. I will use those. I still have to run the 120v wire.

Appreciate the feedback.

[DouglasReid]

Originally Posted by dbareford

Thanks for the info. I am pre-wired for a fan back there, so I have 12v wires. I will use those. I still have to run the 120v wire.

Appreciate the feedback.

If you use it for the 2nd AC you will have to feed the wires to the thermostat location.

My second AC does not have a thermostat, just a three position switch to select three fan speeds a in AC mode and 3 in heat mode. It has a Heat Strip for heat, it is not a heat pump.

[JP Camper]

Originally Posted by dbareford

Thanks for the info. I am pre-wired for a fan back there, so I have 12v wires. I will use those. I still have to run the 120v wire.

Appreciate the feedback.

In this case, it sounds like you only have 30A service? If that is the case, you'll need to run a completely different 120v line that will have to be separate from the remaining power supply. You can install a dedicated 120v line by installing one of these:

https://www.ebay.com/itm/Marine-Onbo...AAAOSwhktawMmt

[gfarmcafe]

Originally Posted by JP Camper

In this case, it sounds like you only have 30A service? If that is the case, you'll need to run a completely different 120v line that will have to be separate from the remaining power supply. You can install a dedicated 120v line by installing one of these:

https://www.ebay.com/itm/Marine-Onbo...AAAOSwhktawMmt

In this case, you'll need an extension cord plugged into the 20 amp outlet or generator. I've read this can be done to supply 120V service to a replacement, residential make refrigerator.

[Retired JSO]

I have an additional Dometic non ducted on my small W&P. I ran the 120 volt power over to a cabinet then forward to the fridge area then down to a male 120 volt exposed near the left rear wheel. I then connect a #10 extension cord to that plug and the 20 amp in the pedestal. Works like a charm.

[James Storm]

The 12 volt is most likely to run the furnace if connected to the same thermostat. Stormy