Fan Circuit/Fuse with dual flex-a-lites

[Janz99]

I have a quick question for you guys running an alum. rad with the dual flex-a-lite fans. I have a full painless harness in my car which only has a 20amp fan circuit. The circuit is fine when cold/testing in the garage, but once the car is hot, or ambient temps are pretty high, it starts to pop the fuse, in stop and go traffic. Obviously the two fans are drawing more amperage then the circuit can handle with the little 20amp fuse.

So the question is, what size of circuit/fuse are you guys using with the dual fans? I was thinking of using one of my spare 20amp circuits and feeding one to each fan. I cant seem to find out how many amps each of these fans will draw at full tilt, but do you think a total of 40amps, 20 per fan, will be enough?

Thanks
Ryan

 

[Hotwheelsjr]

Typically any set of dual fans will pull a 30-50 amp initial surge and then run around 20. As long as your wiring can handle the amperage, you should have at least a 40 amp maxi wired in.

 

[Janz99]

The relay will handle 50 amps, the wiring to and from the painless will handle 30amps no problem. Maybe ill use 2 30 amp circuits and call it a day.

 

[Janz99]

So I found the fans on the actual flex-a-lite web site.

http://www.flex-a-lite.com/auto/html/low-pro-puller.html

According to their site, the dual fans draw 14-22 amps. This would explain why when my car is warmed up in the garage, and heavy airflow it seems to work just fine. Once I got into stop and go traffic when everything was heat soaked, it must of started drawing on the high side of that 22amps, ultimitly blowing my fuse.

The wiring on my painless is all 12 gage wiring, so it should hold 25 amps no problem through the fan circuit. I think I will try that first and see if it holds. If not, ill have to wire up another relay and use another circuit to provide 30-40 amps.

 

[Hotwheelsjr]

Yep -- give it a shot. That 14-22 amp draw they claim is sustained draw -- the initial surge when they turn on is a bit more...that's what will blow your fuse if it's under rated. Best way to tell for sure is with a multimeter...check your draw both when they turn on for the initial surge and after they get running for your sustained draw. I've seen "stock" fans in today's cars pull an initial surge of nearly 60 amps!

 

[Janz99]

I was going to put my multi meter on the fans last night to see how much amperage they draw on start up, but its only rated to 10amp max, so thats a no go. I also found that there is some sort of break in the wire that goes from my relay to the fans last night, this might also be causing me problems.

 

[Andre-2]

Put each fan on a separate circuit never had a blown fuse since I did that. Before I even used to melt the fuse holder.

 

[Janz99]

^^^ What size of circuit are you using for each?

 

[KicknAsphlt]

The Hayes controller that I wired up uses a 25A fuse on the primary fan wire....so I wired in another 25A fuse on the secondary wire for the second fan motor.

 

[SWD Fredester 3]

There is a thread on here about wiring the fans, it's been awhile since I read it, I guess you could use search. You want to run dual 30 AMP fuses for the fans.

 

[Janz99]

^^ I remember seeing a thread about it awhile back, with the guy who has the red wide body supra. He was having a similar issue, but when I searched for it, I couldn't find the thread.

 

[Andre-2]

30 amp

 

[Janz99]

After working my ass off last night wiring in another relay/circuit for the fans, it turns out that one of my fans is no good. It spins, but only about half the speed of the second fan, and it seems to be pulling a huge amount of amperage. Even with just the single fan wired to a 30amp circuit, it pops the fuse.

The other fan works just peachy, so for shits and giggles, I swapped the fans from one circuit to another, and it still pops the fuse on the other circuit.... I guess its time to replace the fan.

I called around to get pricing on the fans, and they want $360 + taxes for the unit. Does anyone run something different then the flex-a-lites that might not be as hard on the wallet?

 

[SWD Fredester 3]

My SC300 came with a set of dual fans mounted on the stock radiator. As I remember the previous owner said they were Ford fans. They work fine with no problems. I went out to see if there was a model # but the only sticker on them said Calsonic-made in Japan. Don't really know if they are a Ford part or after market. Guess you could search Calsonic and see what comes up.