Electric Fan sensor temperature and location input

[Maniak]

There has been some good interest in Electric Fan recently and while installing this latest electric fan I noticed that there are a few different schools of thought of where to put the sensor and what temp to run the e-fan.

Some people run the sensor in the intake (Engine coolant temp) and they seem to turn the fan on 15 degrees above the the thermostat temp.

Others run the sensor in the radiator with the probe near the radiator inlet.

The 3rd group I see is people who run the sensor in the radiator but with the probe near the outlet (coolest water)

I'm looking less for the "type" of controller people are using and more towards Where is the sensor and at what temp is it running full speed and at what temp will it turn off the e-fan. Also, What temp is the thermostat and what temps is the vehicle running. Is this the final configuration and are there any issues. Possibly even "why" you went that way.

For example, We just installed an e-fan (taurus) on the tow rig (full size ford van with a 460 motor)...

Thermostat: 195F
Probe Location: Engine

Fan on temp: 205F ish

Fan off temp: 194F ish

Issues: Freeway driving temp (at 65mph) is 203-ish which means if the fan is on when I get on the freeway it doesn't turn off. In order for the fan to turn off when on the freeway I'd have to raise the turn on temp to 210F or so. I've seen this configuration on some rigs but 210F for a fan turn on temp "feels" outside my confort zone. I know some people that run the turn on at 215 of "engine temp" but that is definitely outside my comfort zone.

I'm thinking (close to doing) that I want the fan to control the radiator temp only (turn on/off lower) and let the thermostat alone control the engine temp. This means putting the probe in the radiator and I'm leaning more towards the outlet. This, in theory, will allow the motor to run cooler since I won't need to let it get as hot before turning on the fan and still allow it to turn off when on the freeway.

~Mark

 

[SoNic67]

Sensor in the radiator fins, close to the outlet as possible. In this way, you will keep constant the water temperature entering the engine. And thermostat will take care of the rest.
If you put the sensor close to the inlet, you will not "compensate" for the outside temperature (that affects the cooler efficiency).

I did replace my original (192F) thermostat with a 180F one - before I was having up to 212 degree water when outside was 100F and full A/C, stop and go traffic.

 

[albi1cnobi1]

I second that thought. Radiator fins close to the outlet is the best spot for a more accurate coolant temp. And my take on set temp is at least equal to, but better a few degrees higher than your thermostat temp. What you're thinking is right, so go with it.

Al

 

[chad551]

Here was my plan.. They are made for 1.5" and 1.75" I need a controller !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&N=0&Ntk=all&Jnar=0&Ne=1%2B2%2B3%2B1147708&searchTerm=400-32082

 

[albi1cnobi1]

How about this.

http://www.jegs.com/i/Auto+Meter/105/2283/10002/-1


Al

 

[Maniak]

Well, I stopped by checkers/orielys and picked up the adjustable Hayden controller with the "push in probe".

I had to extend the wire on the probe so it could reach..

I installed it in about 3" from the bottom tank (has a top/bottom tank) about in the center of the radiator.

I turned up the temp on the fan to the point where it would still idle at around 195-ish. One of my concerns is I want it to turn "off" the fan once I get moving if it is already on. The way I had it yesterday it would not. I can lower the temp of the fan but the motor only runs a couple degrees cooler and the fan runs more often.

At idle....


Playing with the throttle trying to get it to run warmer (with the mechanical fan it would start to overheat if I did this).


I have the temp sensor aimed below the fan/shroud between the probe and the outlet. You can see how fast the fan pulls the temp down.



I looked into the lower radiator hose type adapter. If I could have used it, I could have kept the orig. hayden controller. The way the lower hose is on the Van I couldn't do that..

For Comparison, I'll load the video of what the temp would do using the probe in the coolant (heater hose, right off the engine).

~Mark

 

[Maniak]

For comparison.. Here is video of the temp swing when the fan probe was reading engine coolant temp instead of radiator temp..

You can see the temp swing here and you can see the fan can cool the motor, its just comes on too late. As it is, its turning off too cool. If the fan was on and I got on the freeway it wouldn't turn off since freeway temp is 203F at 65 (2500 rpms).



Soo, I "think" it somewhat confirms that is it much better to run the fan off the radiator temp and not off the engine temp.

~Mark

 

[SoNic67]

The engine temperature has a certain "inertia" and that's why you have the temperature swings. You are reading delayed the temperature that you are trying to adjust with the fan.
Reading the temperature close to the exit from the radiator is a way faster reading of the cooling effect of the fan.
I think I will do this mod myself - I still have the original mechanical fan on my Explorer.