Twin fan setup

Hello,


for my 1.8t conversion I have got a skoda felicia 1.9d radiator to locate the outlets to the near side. With this I have purchased a couple of slim fans, both 80w and i am looking for advice on wiring them in.

Current mk 1 wiring is as follows:

Red wire from 30 amp fuse in fusebox goes to temp switch (2 pin)
red/black from temp switch to rad fan
brown from fan to earth.

For the time being I wish to keep the 2 pin switch (single speed) and have both fans on full speed when the switch activates. Can this be done like a daisy chain or will this overload the current fuse/relay, esp on startup? Would I be better running 2 stand alone relays near the battery ? If so any recommendations for waterproof units ?

cheers

pippo
 

I've been running 2 x 10" 80W slimline fans in my Golfs for years, mounted on a 66cm Caddy radiator. Wired as you described, no relay, and it works just fine. I've always been toying with the idea of using a dual temp switch and running one fan on the lower temp and then kicking in the 2nd fan on the higher temp. With my ABF throttle setup I'm running a alu low level radiator with 3 x 7" 80W fans, on this one I'm switching them through a 40A relay mounted on the radiator cowling, using the temp switch to operate the relay which then powers the fans. I fitted the relay to protect the switch. Modern fans are a lot more energy efficient than the old Mk1 fan so even with 3 fans the existing fan feed is more than enough.

Cheers torker,

I will try wiring them in direct and see how I get on. 

I was planning on using resistors to bring both on at half speed for low temp switch and full throttle for high temp. 

Pippo

Pippo said

Cheers torker,

I will try wiring them in direct and see how I get on. 

I was planning on using resistors to bring both on at half speed for low temp switch and full throttle for high temp. 

Pippo

That will work, my BMW used a resistor to bring in the fan on low speed when the aircon was switched on and full speed when the coolant got hot. If you can find one of those resistors (off a E28 BMW) it will simplify your wiring somewhat.

I have twin fans on my abf conversion but used a relay so the temp switch is just a switch if that makes sense.

bit of a thread resurrection here

but the correct way is to first check the amp rating for the aftermarket fan(s), and make the load doesn't exceed the fan fuse which is 30a. if it does fit a relay, if not dont bother

fitting a relay regardless isnt a bad idea though, especially if the fusebox or wire is past its best.

alternatively if your fusebox/wire is bad just run the live for the fan direct to the battery with suitable gauge wire and inline fuse to suit the rad fan requirements. Aftermarket ones tend to be lower ampage so you can reduce the wire/fuse accordingly