Air Conditioning Wiring

[Eldorado]

Hooked up and charged my air conditioning system yesterday and it performed well. Cold air with good fan velocity. One problem did occur. The high pressure side of the system got up to almost 400 PSI. Engine was running but not radiator fan because the engine had not come up to temperature to kick on the fan. How do you ensure air is flowing through the condenser (mounted in front of the radiator) when the fan is not running....What is the most effective way to run the wiring....

Thanks

[65 Cobra Dude]

Eldo,

I am currently working on the same thing, with the same symptoms on my roadster. I took it to an AC expert and he said the fans absolutely have to go on as soon as the AC compressor turns on. I have a coyote motor in mine and am trying to figure out the wiring. When the fans did come on because of engine temp, the high side went back down to 150 or so and blew cold air.

I'll be watching this thread and hopefully someone with much more experience than me jumps in.

Henry

[Hankl]

If I'm not mistaken, there should be a relay installed to activate the fan or fans, some systems have that relay/switch on the pressure side of the system.
So that the system turns the fan on when you turn on the AC. If you're running a Fuel Injection system, there could also be a trigger for that within the control module.

Hank :cool:

[CHAZC5ZX]

Yes the fan MUST come on with the compressor. I used A Hayden 3647 fan controller it has A wire that connects to the compressor for that purpose.
Chaz.....

[loeffler1]

It is called a trinary switch and I installed mine at the top of the dryer. When AC PSI gets too high it switches the fan on. Best to wire through ground like temp switch and dash switch if you have one. Vintage Air sells them in their catalog.

[CraigS]

I also recommend having the fan come on when the AC compressor is engaged. If it only comes on when the coolant warms up that will be way too long for the AC system.