[1966geeto]

Finished installing my new Vintage air system going to add an extra cooling fan what do you guys recommend keying the fan to com on with ign or using a trinary switch the kit only comes with a low pressure switch thanks for the input.DON't want to evacuate and charge and then have to put in a switch.

[quicksilver97ta]

Same situation, I wish I had went for the trinary switch to have that option but I’m not going to evac and recharge just to install it. So, the options are to wait for some other reason to evac but that hasn’t happened and (knock on wood) I don’t see it happening as my system has been together for over 3 years now. Next option is to use a coolant temp sensor to relay a switch because that’s what will happen, coolant temps will go up. This only happens when the car is not moving and fwiw I have optimized the stock cooling system as much as possible. Surprisingly, a/c cooling is barely affected, I assume that is because the condenser is in front of the radiator. And some would consider the coolant temps acceptable but after driving the car in the 180 to 190 range and then stopping for gas, car running w/ a/c on (family in the car), temps will go to 210 if left long enough. I would like an electric fan to kick on and pick up the slack.

[Squidward]

You could try a relay that turns on with the compressor clutch, and in turn switches power to your fan.

[rexs73gto]

Using a switch off of the compressor is the way a lot of the cars turn on there secondary fan, thats the way I'd do it. That way you know the fan is on when it's actually needed.

[1966geeto]

I was under the impression that the trinary switch turns on the accessory fan according to Vintage Air I have to add another temp switch and a relay witch is not making any sense to me I thought the trinary switch senses high head pressure and in turn tells the fan to come on correct me if I'm wrong going nuts just finished wiring the whole car.

Could use a little help..

[Joel Koontz]

Originally Posted by 1966geeto

I was under the impression that the trinary switch turns on the accessory fan according to Vintage Air I have to add another temp switch and a relay witch is not making any sense to me I thought the trinary switch senses high head pressure and in turn tells the fan to come on correct me if I'm wrong going nuts just finished wiring the whole car.

Could use a little help..

IMO the best arrangement is to have a temp switch to turn the fan on if the coolant gets too hot and a trinary switch to turn the fan on if the compressor head pressure gets too high. Both should be wired through a relay.

Running the fan anytime the compressor is running is how some cars are wired, but when you are going down the road at 60 MPH there is no need to have the fan running. Using a trinary switch will only have the fan running when the compressor needs it.