Electric fan install

[Ramiro0727]

Hello,

I purchased a 16" American Volt Electric fan. I was wondering when I install the fan. Can I piggy back off the thermostat switch and have on wire going to the fan and the other wire going to my temp gauge in the dash cluster? Or should I get a temp sending unit and mount it on the drivers side of the engine and run that wire to me temp gauge in the dash cluster?

Thanks,
Ramiro

[Andy4639]

Most temp senors work off ground.

So if you want the fan to work put a hot wire with relay in line and use it as the ground. The only problem I see is it will be on anytime the temp senor is grounded unless you use a switch also in line to turn it on/off

[rcazwillis]

You need another sensor. The sending unit for a gauge has a variable resistance. A fan needs a on/off sending unit. Basically, reach this temperature and ground the wire.

[Andy4639]

The temp gauge itself has nothing to do with the senor grounding. The senor goes to ground and the gauge reads what ever the resistants is but for the fan it's grounded. I would hook it to another senor also are if the truck has ac hook it to the compressor switch through a relay.

Whatever way you do it make sure and use a relay. Fans take a lot of amps.

[19671972C10]

And dont hook fan power into ingnition power like i did and fried my fan control. Btw Advanced Auto parts sells fan control kits.

[Ramiro0727]

Thank you all for chiming in. I think I'm going to use a temperature sensor on the driver's side of the engine block for my dash cluster temp gauge. Also my Electric fan did come with a relay switch that I will be using.

Thanks again,
Ramiro

[VetteVet]

The temperature gauge sender operates off variable resistance from about 500 ohms cold to 230 ohms hot so I doubt that the relay would ground as the water temperature rises to where you want the fan to kick on. Not only that but if it did fire the relay the sender wire to the gauge would be connected to positive through the relay coil. That might not be healthy for the temp gauge. You could overcome that with a diode which some relays incorporate.

The other problem you might see is the voltage induced when the water temp cools and the relay shuts off that would spike to the temperature gauge through the sender wire.

If I can think of any other reasons not to do it I'll post them. LOL

[Ramiro0727]

Originally Posted by VetteVet

The temperature gauge sender operates off variable resistance from about 500 ohms cold to 230 ohms hot so I doubt that the relay would ground as the water temperature rises to where you want the fan to kick on. Not only that but if it did fire the relay the sender wire to the gauge would be connected to positive through the relay coil. That might not be healthy for the temp gauge. You could overcome that with a diode which some relays incorporate.

The other problem you might see is the voltage induced when the water temp cools and the relay shuts off that would spike to the temperature gauge through the sender wire.

If I can think of any other reasons not to do it I'll post them. LOL

VetteVet I'm going use the relay switch for my electric fan. As far as the temp sensor it wii hook that straight to my temp gauge on my dash cluster. If that will work.