Amps running A/C

[Amg]

I have a 2020 Interstate Lounge. When I run my A/C either on shore power or generator, it reads 18 AMPs with compressor on. Nothing else is on except battery charging and refrigerator that runs on DC. The generator produces 20 AMPs. When the compressor starts the surge uses about 4 or 5 more AMPs. Just seems to be cutting it close to a circuit breaker trip if that is normal.

[GetawA-S]

What size and model is your AC?
My 13.5 KBTU/hr Dometic In a 23FB pulls 4 A for the fan and 12 A for the compressor and fan together.

[Pahaska]

Originally Posted by GetawA-S

What size and model is your AC?
My 13.5 KBTU/hr Dometic In a 23FB pulls 4 A for the fan and 12 A for the compressor and fan together.

Exactly the same for mine on my current and former AI. That's with the fan on high.

[Amg]

I have a 13.5 unit. If I am drawing 18 Amps in total is it possible that the refrigerator and battery charger are pulling 6 amps or is there another draw I am not considering. I do live in Florida and wonder if that affects the draw

[Pahaska]

Originally Posted by Amg

I have a 13.5 unit. If I am drawing 18 Amps in total is it possible that the refrigerator and battery charger are pulling 6 amps or is there another draw I am not considering. I do live in Florida and wonder if that affects the draw

Refrig and freezer are very light loads on the 120 volt feed. Given the voltage conversion, the two of them, if the compressors happen to be running at that moment, might add up to half an amp of 120v.

The battery charger is another thing. Depending on the setting and state of the batteries, it can draw a few amps.

[GetawA-S]

As with the AC, power draw varies with model and size. My Dometic 5CF fridge draws less than 2A on 120 V, when the heater is activated. If you have the NovaKool compressor style, it’s about 1/2 A.
An Inverter pulls about an amp with no outlets in use. Convertor load depends on battery condition, but should drop off when the battery is charged.
Experiment! Turn things off and note the effect. Any type of heater will draw a lot of power. You’ll want to know all this before you need to rely on your generator.

[Amg]

Thanks everyone

I will do a test this weekend turning on loads. There is nothing I can turn off easily. I can turn off refrigerator but can’t turn off battery charger and still have amp display. It could be the amp meter

[Amg]

Originally Posted by Pahaska

Refrig and freezer are very light loads on the 120 volt feed. Given the voltage conversion, the two of them, if the compressors happen to be running at that moment, might add up to half an amp of 120v.

The battery charger is another thing. Depending on the setting and state of the batteries, it can draw a few amps.

The unit has been plugged in for AC for over a day so the batteries should be charged. The battery charger was set by the factory and not changed. I purchased unit in March this year and know batteries are good. Tested them at purchase and unit has always been either plugged in, on generator or motor running, except when parked for a few hours.

[Bill M.]

I do not have an Interstate. But my experience with the power converter in my trailer tells me that your reading is probably correct and it is drawing 18 amps. My power converter often draws 7 or 8 amps or more. And when you are running the AC on the generator you probably have not been plugged in for a while and the batteries are accepting charge at a good rate.

[Boxster1971]

Originally Posted by Amg

I have a 2020 Interstate Lounge. When I run my A/C either on shore power or generator, it reads 18 AMPs with compressor on. Nothing else is on except battery charging and refrigerator that runs on DC. The generator produces 20 AMPs. When the compressor starts the surge uses about 4 or 5 more AMPs. Just seems to be cutting it close to a circuit breaker trip if that is normal.

That sounds very normal. Just be glad Airstream has now installed a Power Control System (PCS) that can handle those surges in the A/C current draw. The one in my 2013 Interstate can't handle it when using the generator. I have to disable the PCS to make the A/C work on generator. The generator can handle those brief surges.

[Amg]

Thanks Boxster. Had a 2016 unit before this and ran about 4 Amps less

[Titus]

Mine pulls about 18-19 amps when the compressor starts then settles in at 15 amps. this is cutting it close when using the generator, but I have never had it trip a breaker or be subject to load-shedding by the PCS, and thus have not seen a need to install a soft-start. My batteries must not have been undergoing bulk charging at the time, as the load was minimal prior to starting the AC.