What's A Good Electric Fan Controller?

stangboy

Founding Member
Aug 31, 1999
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New Orleans, LA
Hey guys,
My Flex-a-lite electric fan controller took a crap when the car was on the dyno. So I need a new(better) one. What's everybody using? Since the Flex-a-lite controller didn't last on the dyno I know it won't last with street driving...especially in the New Orleans summer heat. What do you guys suggest?
 
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You need to turn the fan on when the AC is on or your compressor will blow your oil/freon all over the engine compartment. There's an expensive flex-a-lite, that is significantly different from the cheaper ones, that does this. The downside is it is pretty large.
Otherwise you have to rig your own AC relay. I suggest the expensive flex-a-lite. But if you don't like flex-a-lite, check out Ron Francis. They have some pretty nice simple controllers. They are really just heat sensing switches that turn on a separate relay. That would make things pretty easy to add the AC switching circuitry in later (they might even help you).

Even better, I suggest upgrading to a mechanical fan.
 
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I've had bad luck with controllers, switched back to clutch fan and never looked back. The small gain you get from it isn't worth the risk of getting stranded on the side of the road, trying to fit underneath the car enough to hardwire the fans with a piece of scrap wire you found in the trunk so you can get home.... Not that I've had to do that before...
 
I've run the FAL 33054 on several cars without any problem. been on my current car for 4 years. I don't like the DCC because.....welll.. Brian. He gives terrible customer service, you have to wait weeks for the part, you get no communication from him.. Also he licensed his technology to Derale if you want one

https://derale.com/products/electri...oller/pwm-fan-controller-push-in-probe-detail

The reason you want a soft touch controller is fans like the Taurus, Contour, and MKVIII can spike up to 60 or more amps at start up and the controllers above will start the fan at 60% rather than full on.
 
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I've had bad luck with controllers, switched back to clutch fan and never looked back. The small gain you get from it isn't worth the risk of getting stranded on the side of the road, trying to fit underneath the car enough to hardwire the fans with a piece of scrap wire you found in the trunk so you can get home.... Not that I've had to do that before...
I did too for a while. I switched to a 75 amp relay triggered by a temp switch in the water neck. Dead simple as far as controlling the fan goes. Extra relay in the glove box, and if the temp switch fails, I can just pull the wire off an ground it. Still may need that scrap wire in the trunk if I have to ground the relay! LoL
 
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I've been using factory fan switches from different makes and models to ground relays to control the fans ( Contour fans ). I'm using another relay that uses the fan clutch signal to switch a relay grounding the high fan relay.

With a lot of aftermarket fans high amperage is drawn to start the fan motors. The Contour fans pull less than 20amps on start up....so 30amp relays work fine.
Different vehicles run different fan switch temps. A quick google search takes care of that.

All of the thermo switches I've ever used failed...usually when I needed the fans the most. Figured, I'd copy what the big manufacturers do. Their systems were designed to last.....but just in case... I have a toggle switch hidden on my column. :nice:

I actually had this post sitting in the post box for two hours...smh.

The amperage on my Contour fans doesn't spike above 30amps, individually. I use two 30 amp relays...one for high and one for low... 60 amps combined. Most factory fans don't have soft start, are set up ground side switching the relay circuit, and carry the load through 30amp relays.

I'm also the village idiot at times....just learnin' as I go.
 
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I actually bought a Leash Electronics single relay board with a 70amp relay on it. The controller had a soft start feature on it so I never installed the relay board. I'm guessing maybe I should have. I'm using a Mark VIII fan and I know it has a pretty big amp draw on initial startup but I thought the controller could handle it. I'll definitely install that relay board now, no matter if the next controller I get has a soft start feature or not. That Derale controller is peeking my interest right now.
 
I actually bought a Leash Electronics single relay board with a 70amp relay on it. The controller had a soft start feature on it so I never installed the relay board. I'm guessing maybe I should have. I'm using a Mark VIII fan and I know it has a pretty big amp draw on initial startup but I thought the controller could handle it. I'll definitely install that relay board now, no matter if the next controller I get has a soft start feature or not. That Derale controller is peeking my interest right now.

I use the dual 70amp relay with my old flex a lite controlller that came with my black magic extreme . It just triggers the relays now and they kick my contour fans on
 
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