Vintage air problem versus computer - Lateral-g Forums

RdHuggr68 · #1 07-12-2012, 06:14 PM

Have a 72 Chevy with Vintage Air GenIV system.The car has an LS motor and the fan only kicks on at 220 degrees. The problem is that when you turn the air on the fan does not come on unless the motor reaches 220. Well that raises all hell with the compressor because the condenser is not getting any air through it.
Without adding another fan for A/C only does anyone know how I can get the existing fan to come on when the A/C is turned on without screwing up the computer?

Thanks , Kevin

**camcojb** · #2 07-12-2012, 07:27 PM

Quote:

Originally Posted by RdHuggr68

Have a 72 Chevy with Vintage Air GenIV system.The car has an LS motor and the fan only kicks on at 220 degrees. The problem is that when you turn the air on the fan does not come on unless the motor reaches 220. Well that raises all hell with the compressor because the condenser is not getting any air through it.
Without adding another fan for A/C only does anyone know how I can get the existing fan to come on when the A/C is turned on without screwing up the computer?

Thanks , Kevin

sounds like you have a binary switch. If you use a trinary switch you get the extra output to turn the fan(s) on whenever the a/c is activated.

**parsonsj** · #3 07-12-2012, 07:48 PM

Quote:

If you use a trinary switch you get the extra output to turn the fan(s) on whenever the a/c is activated.

I like to use trinary switches for that reason too. Vintage Air sells 'em.

http://www.vintageair.com/2012catalo...Page%2087).pdf

RdHuggr68 · #4 07-12-2012, 08:06 PM

i put a trinary switch in with the intention of adding another fan (pusher) in front of the condensor. I did'nt know I could tie it into my existing fan. Any help would be appreciated.
Thanks, Kevin

**parsonsj** · #5 07-12-2012, 08:09 PM

Quote:

Any help would be appreciated.

Follow the link I posted above... it has a wiring diagram and everything.

RdHuggr68 · #6 07-12-2012, 08:22 PM

Quote:

Originally Posted by parsonsj

Follow the link I posted above... it has a wiring diagram and everything.

Thanks John I appreciate your help!!
Kevin

Z06vette · #7 07-19-2012, 08:36 PM

Not sure if you had a factory harness reworked, or what computer you have. I'm using a modded factory Fbody harness with factory computer. You can have it tuned to turn the fans on earlier. Also, there is an AC feed that you can hook to the blue wire on the VA harness for the compressor.. This will turn on the fans as soon as AC is turned on. Or use trinary switch as mentioned above.

RdHuggr68 · #8 07-20-2012, 09:13 PM

I could be wrong but what if the compressor circuit turns on the fan and when computer sees the engine temp reach 220 degrees and turns on the fan circuit.Isn't that a major problem.........?

**camcojb** · #9 07-20-2012, 09:16 PM

Quote:

Originally Posted by RdHuggr68

I could be wrong but what if the compressor circuit turns on the fan and when computer sees the engine temp reach 220 degrees and turns on the fan circuit.Isn't that a major problem.........?

nope.

**GregWeld** · #10 07-21-2012, 08:09 AM

Quote:

Originally Posted by RdHuggr68

I could be wrong but what if the compressor circuit turns on the fan and when computer sees the engine temp reach 220 degrees and turns on the fan circuit.Isn't that a major problem.........?

They both work via shorting (switching) the ground circuit... once it's a circuit it makes no difference which one is causing the switch.