Can you run dual electric fans on one relay ??
 

I have a 99 Ranger shortbed I bought two single 10" fans on eBay and wanting to know if one relay would run both to save on expense and have that much more wiring to hid .

I have a buddy that has a four core radiator in an old fairlane he told me one fan probably be enough because he doesn't have any fan in it and it only gets hot a long stoplights

Depends on the wiring for the relay and what the relay is rated for.

If you have two fans pulling 8amps which is a combined total of 16amps and a relay rated for 10 amps you're asking for trouble.

If the relay has multiple output pins and is rated for the load, you can run two fans

I have two relays on mine for each fan at 50amps each.They are two 10" plus one 8".If you run two fans off of one relay get a 50 amp and run at least 10gauge wire to the fans,and to the relay.To little wire will heat up and catch fire maybe.

As stated, find out the amperage rating of the fans first.
Std Automotive relay can be purchased in any amperage rating and use factor, HD relays for Fan are almost a must.

If the fans are rated for 30 amps then 10-ga wire is good but if more than that consider running heavier wire say 8-ga because you want the fans to run as fast as needed to keep you cool and smaller wire will reduce the amperage causing heat and maybe even a fire. Unless you want to wire each fan separately then smaller gauge wire can be used. Wiring the fans separately is a good idea for just in case one fan or a component burns out.
12-ga wire = 20 amps
10-ga wire = 30 amps
8-ga wire = 50 amps
Relay can be larger than the actual current draw, can’t hurt.

Cooling fans draw a lot of amperage and the fan itself is a necessary component for the engine to run cool and get you home so make sure to over size all of the component and the install will get you there and back.

A couple of other thoughts:
Fuse the main power wires on pin 30 from the battery and the relay power wire on pin 86 as close to the power source as possible.
Gauge the wire and relays for the largest amperage draw.
Size the fuses based on the smallest amperage draw.
The relay power can be from the battery or any power source under the hood BUT the main power for the fans (pin 30) HAS to be from the battery.
It is better to use extra components, i.e. relays, fuses and wiring then to get towed home or worse have your ranger burn up.

Sorry if this has been said before or if this is too much info for the project but I have always found that it is better to be safe than sorry.

I run dual relays and a single fan on my mustang lol

heres a similar diagram to what I've done: http://www.product-engr.com/pe_1050.htm

Its a nice setup because one relay can crap out and I can make it around just fine using the second. I keep a handfull of relays in the glove box just incase

Hey how did this work out ?

Did you get the install completed or decide not to do it ?

If you did install the E-Fan, how did you wire it up ?

Remember over-kill in a system that is needed to operate the vehicle is a must-do.
Sitting at a traffic light and not getting too hot is one thing but when you depend on the E-Fan to cool you on a trail run and get you home is another.

ltr
Let the site know how this worked out for you ?

I got them installed I used a 50 amp thermostat kit I found on E-bay easy install mounted relay next to battery. My fans are rated like 8-10 amps per fan I don't really remember but it was way under the 50 amp rated relay . I have it hooked up to where if I turn the truck off when it's hot the fans will stay on till the reach there 180 thermostat
I believe in over kill like you where saying better be prepared then stuck on the side of the road

Good to hear things are wrkg out.
Two relay setup would have given you a backup.

ltr

I have some aftermarket Temp Gauge on it to keep an eye on it

Good to hear it is installed and working.

Wirelessly posted

Scrambler if I get a Efan you should assist in the install

They will probably run backwards if I hook them up.
To me E-Fans should be used only if you think you will gain some power, which in little engines like ours it won’t be much, and/or if space is a problem like when you put in a V-8.
For me an E-Fan spells “ELECTRICAL NOISE” in caps… so less of that is good for an Amateur Radio Freak; CBs too !

If at all possible stay with the mechanical fan but if you do sw I can help… along with all of the electrical genius’ on the site and do it as Idrivebadassfords stated he did, the fan should stay on after the engine is shut off to cool the radiator…