Chevy & GMC Vans

HuntnFreak,
Without running the AC during certain functions, you will lose the ability to remove moisture from the defrosting air.
I suppose that you could wire an open into the low pressure switch, and that would keep the ac compressor from coming on.
It will be just like a car that didn't have ac, or has had the ac system removed.
Good Luck, and Keep us Posted, Jim

huntnfreak wrote:I was wondering if anybody knew at what temperature the air conditioning compressor stopped kicking in at? Freezing point or lower or higher? Hate running it at the moderate temperatures using heat to defrost and the compressor running. I'm sure there is a reason for that but in the name of fuel consumption, I try to be as frugal as possible. Anybody ever use a switch in line to manually shut it off to turn it off during fall times or is this a bad idea?

Hello hunt;

The compressor comes on anytime you put the selector switch in defrost. That is to help keep the windshield clear. As was said, just put a on/off switch in the low pressure switch circuit. The low pressure switch is on the accumulator. For that matter, you could just unplug the switch. That would keep the compressor from coming on. There will be no harm done to the AC system if you do that.

Drive safe,

Dan Harriman
91 Safari Shorty RIP
Orange Texas

The only thing I would be concerned with is not cycling the compressor to keep it and the internal seals lubricated. For what a blown compressor costs, you will never save that much gas over a winter. The windshield will not defrost as fast, especially in really wet fall/spring weather. I would leave it as is.

I'm pretty sure the owner's manual says that even if you don't need A/C, you should run it once in a while for maintenance.