Question about a motorhome's dash air conditioner

[Craig95005]

I think our motorhome may be a bit light on rooftop air conditioning when we get into the summer.

My question is this. Will running the dash air conditioner with the engine off but the coach plugged in to shore power work without draining the battery? With the engine off, I know the blowers work, but will the AC also cool from just battery power, without the engine running? And it's seemed to me in the past that the battery up front gets recharged from shore power - is that also true? If it is, I should be able to supplement my cooling without resulting in a dead battery. Thanks.

[Bill_Satellite]

Craig95005 wrote:
I think our motorhome may be a bit light on rooftop air conditioning when we get into the summer.

My question is this. Will running the dash air conditioner with the engine off but the coach plugged in to shore power work without draining the battery? With the engine off, I know the blowers work, but will the AC also cool from just battery power, without the engine running? And it's seemed to me in the past that the battery up front gets recharged from shore power - is that also true? If it is, I should be able to supplement my cooling without resulting in a dead battery. Thanks.

The dash air will not work AT ALL without the engine running.

[old_guy]

to answer the question if you run the fan without the motor running, yes you will drain the battery. you will find yourself with out enough battery to start your MH in the morning

[dougrainer]

You need to post year/brand/model of your motorhome. THAT will help us determine if you have a problem with your roof top units. You stated one was replaced, maybe it was not installed correctly, OR you have a problem with the other AC unit. If it is not cooling correctly now, what do you think will happen in 90 plus temps? Find and fix the problem BEFORE you find that out:B Doug

[Ski_Pro_3]

If you have slide-outs and can function with them in, that will decrease the size/area needing chilling and I've found it really helps.

[MrWizard]

if you want to move more 'AIR' around, get some 120v fans

close the curtains, put out the awning, turn on the a/c early in the day

don't wait for it to get 90* inside before you start the A/C

[IBcarguy]

Forget about trying to run the cab AC without the engine on. All you will be doing is pushing hot air into your motorhome. And yes, you will be putting extra demand on your batteries although your inverter will be recharging them when shore power is plugged in. Your truck's AC is only designed to cool off the cab (driver and passenger) when underway.
You already said you have 2 AC units and short of adding another one (which is an overkill), it sounds like you have more than enough AC for your unit.
If you are plugged in, run your AC units, close your curtains, keep your windows closed and you should be comfortable enough. If you want a 62 degree room, reserve a suite at the local highline hotel.

[Craig95005]

Thanks for the information. Didn't think that would work, but never know unless you ask.

We have two AC's and things are fine now, but it's not getting over-cool at present in late March, and we'll be going up along the East Coast (in Charleston now) in the summer. How about turning on the dash blower without the AC - will that drain the battery?

We already have double pane windows, and the AC's seem to be working well. (One is new.)

[gbopp]

Now that you know your dash air does not work work the engine off, consider insulation for the RV windows to help keep the sun heat out.
Reflectix or something similar does a good job.
Also make sure your A/C filter is clean and the unit is working properly.
Can you install a larger or second air conditioner?

[Lwiddis]

Augment your RV A/C after you are sure it’s inadequate.

[IBcarguy]

For the cab AC to work, the engine must be running. The AC compressor is belt driven off the engine. The fan will run with the key on, but without the compressor turning, no chilly air.

[Phil_M]

No the compressor for the dash ac is run by the engine so no cooling only fan with engine off.