2nd Gen Non-Engine/Transmission Fan Removal / AC Relay Disable

[Midnite]

When I removed engine fan on my '92 for winter, I just unplugged the AC relay--is this possible on the 2000 truck I just bought?



I've read the stuff on Dave Fritz's site about installing a separate AC switch, but I'd like to just unplug a relay for this winter and worry about doing the switch next summer (when I can work on my truck when it isn't -10 outside!)



Thanks,

Mike

 

[illflem]

Pulling the relay will work fine but to be on the safe side I'd suggest you reinsert it at least once a month and run the A/C for a little bit while the truck is moving.

Running the A/C occasionally keeps the components lubed and prevents seals and other rubber components from drying out.

 

[parcher]

I'd leave the relay in. In some situations the a/c really helps defrost the windows.

 

[illflem]

My experience is once the temps get below freezing the outside air is so dry that it makes little difference if the defrost has A/C or not. Better to put up with a little slower defogging than damaging your A/C system while running fanless.

 

[Midnite]

Hmm... does the AC only kick in in the AC and Defrost positions?



If true, then I should be able to leave the relay in, and only turn it to those positions when the truck is moving significantly (ie, more than 10 or 20 mph).



Mike

 

[David Oxland]

This brings up a puzzle that I never really understood. The AC doesn't know whether your fan is in place or not. The only thing that happens is the viscous coupling closing and fan goes. AC has no communication with the fan or it's clutch and I'll bet that it takes some time for the condensor heat to make the fan clutch close. And I thought that the main thing affecting the fan clutch would be radiator temp. There must lots of occasions when the AC cuts in and the fan clutch isn't closed. I think that the AC must just be limited by the condenser HP switch (high pressure) as a normal function not just a safety function.

 

[Loren]

Mike,



I don't know about your older truck, but on your 2000 truck, the only selections which turn off the air conditioning compressor are OFF and floor only.



All selections that include either defrost or dashboard vents will cause the air conditioning compressor to cycle on.



My 1995 truck doesn't do this, but the 2000 does.



Loren

 

[illflem]

Loren is right, most all positions on the newer trucks run the A/C, you'd be better off to pull the relay or install a switch.

 

[Newf Limo]

If I pull the fan off, must I do anything with the a/c? I was just getting ready to pull the fan off today. . .