People with Electric fans - how do you control them?

[Canadian1968]

For those that are running an electric fan setup. How are you guys controlling your fans?

I am currently running 2 fans wired to a single thermal switch, so they both turn on at the same time.

Doing some browsing I have found various different controllers out there. One by Dakota Digital that allows for individual fan temp settings and another one from Derale that actually controls the speeds of the fans so they are not just running at 100% all the time.

Curious if any one has use any of these controllers or are most people just the running single point thermal switch??

 

[snakeoil24]

First thing do you have a shroud

 

[BeepBeepRR]

I have used the Holley Sniper setup to control fans on one car and on another I used a thermal switch for each fan both set at different temps. Like one at 185 and the other at 195. Using those numbers as examples. I don't actually remember the temp settings I used.

 

[Aron Gleason]

I just wire my electric fan to a toggle switch as I have a engine fan.

 

[493 Mike]

I have 4 fans and am controlling them in pairs through the FAST EFI control module. Not finished yet but, that is the plan.
Mike

 

[Canadian1968]

First thing do you have a shroud

Yes I have a shroud . The system works quite well really. I upgraded the fans this winter as I did feel the old ones where reaching their limit on hotter days . ( amazon fans pulling 7.5 amps each ) . I was able to replace just the motor almost doubling their power .

When I had the motor running to test them out everything is fine but they do cycle fairly quickly . So the temperature is fluctuating approx 15 degrees . Mind you this was just some idle time in the garage and the ambient air is obviously much cooler then it will be in summer. I guess what I am really asking is does it really matter if the temp would constantly fluctuate or would it be better to try and keep it more consistent.

Obviously going to run it how it is and see how it does in real world conditions. But was interested if anyone has tried any of the other controllers

 

[diesel_lv]

I believe Volvo has a 2 temp switch. The PWM (pulse width modulation) is good if you are worried about the fan's longevity. When I was running electric, I just had both come on at the same time. Strong alternator, 50 amp relay n 50 amp circuit breaker. 10 guage wiring n never a problem. Google Volvo electric fan relays. Plenty of write ups on the 2 speed sensors

 

[Roger63]

I use this it connects the ground wire on the fans at 185 and disconnects at 165.

 

[Don Frelier]

I have the msd atomic EFI on the charger.
I have two small cheapie pullers that I set for 190 and a nicer pusher set for 195.
The EFI grounds a two relay coils which powers the fans.

Usually just driving on the road I'm between 185-190 so the fans only come on at a stop or slowdown.
I'm just using a 22" cheap radiator from eBay.

 

[forphorty]

Toggle switch

 

[David Womby]

Single adjustable thermostatic switch - the type that has a probe you stick between the vanes on the radiator. I also have a switch on the dash to turn the fan on manually.

I plan adding a delay relay to run the fan for 3 minutes after engine shutdown too.

David

 

[Nacho-RT74]

you can use two thermal switches one for each fan, or use a dual range thermal switch... wired like this:

I made this diagram with switches using ground to trigger them. Some switches don't get the chassis ground source but get a prong for it

Somewhere I saved an image of a variety of thermal switches to be used... searching and will post.

EDITING
Found it:

diff temp ranges... match your needs.

sure will need thread adaptors to use one of these

 

[451Mopar]

I used the Dakota Digital fan controller. It is nice that you can program it to use any sender, and the on/off temps, and even have a timer allowing the fan to run after turning off the engine.
Now that the car is EFI, I just use the EFI controller.

 

[6PKRTSE]

I have one come on automatically at 180 degrees through the Racepak and the second fan I can turn on when in traffic off of the overhead control panel but haven't needed it yet.

 

[Canadian1968]

you can use two thermal switches one for each fan, or use a dual range thermal switch... wired like this:

I made this diagram with switches using ground to trigger them. Some switches don't get the chassis ground source but get a prong for it

View attachment 1264332

Somewhere I saved an image of a variety of thermal switches to be used... searching and will post.

EDITING
Found it:

View attachment 1264334

diff temp ranges... match your needs.

sure will need thread adaptors to use one of these

I can't seem to find those sensors . I am trying to find the 2t001 - 550 604.... but those numbers don't seem to bring up what I want.

I keep getting referenced to a holley part for 550 604 number .

any idea on year or model that would take those sensors??

 

[Brewzer67]

I run the Derale box and it works ok. I do have a few occasions where the temp gets above the level where the fans should start but they don't. This is usually only after initially starting the car. If I use the bypass switch the fans start and everything works fine from that point forward. I now just incorporate that into my starting routine. I start the car, I flip the switch and run them manually for a few seconds to confirm they are working for the day, then I set it back to auto and it is fine from there out. The box seldom runs the fans at full speed. Usually it starts them out at low speed and that is generally enough to keep the car cool enough. It will go to high speed on 80+ degree days when I have to idle in traffic but that is about it.

 

[Nacho-RT74]

I can't seem to find those sensors . I am trying to find the 2t001 - 550 604.... but those numbers don't seem to bring up what I want.

I keep getting referenced to a holley part for 550 604 number .

any idea on year or model that would take those sensors??

I think they are used on European cars... hence the metric thread. The website I found those was from Italy as far I recall.

Anyway those are just a suggestion. Pretty sure there must be more options around.

 

[Nacho-RT74]

I plan adding a delay relay to run the fan for 3 minutes after engine shutdown too.

David

That's a good idea. I didn't include it on my diagram because didn't know what kind or PN to search it. I don't think 3 min is necesary. 1 should be more than enough, althought once coolant is cooled down, will stop way before than those 3 or 1 min.

 

[Erik Morris]

That's a good idea. I didn't include it on my diagram because didn't know what kind or PN to search it. I don't think 3 min is necesary. 1 should be more than enough, althought once coolant is cooled down, will stop way before than those 3 or 1 min.

What is the purpose of letting the fan run for a few extra minutes after shutdown? The water pump is off so it isn't moving any coolant through the motor...?

 

[Nacho-RT74]

Actually after stops the engine the coolant into the block keeps heating faster due the same reason you mention, being circulation stationary or slowed down. This of course increases temp and pressure. The pressure and temp variation between block and radiator being cooling down by the fans can still push some coolant circulation. You can check modern cars keeping the fans on if thermal switch keeps on the temp range for afew seconds/minutes after shut off ign switch. So is not a crazy idea or anything new.