Adding electric compressor to run a/c while truck is off?

Hi Everyone,

Most APU systems add their own a/c system. It involves an outside box and an inside piece separate from the trucks normal A/C. On the battery APU's they have a completely separate system as well. With the engine off, the truck a/c wont work because the compressor is not turning.

So my question it. Why couldn't i add another compressor with a 400-600 watt 12 volt motor attached to it. (maybe a 2 speed motor) I would then use the trucks entire ac system with a secondary compressor controlled by a switch. I would use the trucks blowers, air ducts, evaporators etc and save on weight. I'd also have a more uniform cooling since it uses the ducts designed by the truck manufacturer.

So, is there a reason this wouldn't work? Is there any reason I could not add a second compressor inline with the engine one? If this worked I would just run an electric motor off the batts while stopped and use the normal compressor while driving. Am I missing something else on how a/c systems work?

Thanks,
Cody

 

Thanks for the info... That makes scence.... Just a shame to have extra equipment that's not really needed.

 

How are the condensers on the add on a/c units cooled?

 

What about a unit like this. Could it be integrated into the existing system?
http://www.masterflux.com/products/condensingunits/?pid=67

 

Yea, thats crazy overkill, the conversion form ac to dc is to much. I'd like a dc unit. Pluss, where are you goign to mount a window unit without cutting a whole in the back of the truck. !0 batts weigh way to much. I'm already planning on buying EOS AGM batts, but they limits me to around 500 watts if I want it to last all night. Window A/c units use over 1000 watts and thats not including the dc to ac conversion.

 

06 Columbia