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The Auto Cool Guy has a better way to control engine temperature.
We use Pulse Width Modulation of your fan to control its RPM. Our sensor monitors the radiator outflow temp and adjusts the fan RPM to keep the outflow at a constant 15 to 20 degrees BELOW the thermostat temp. This way, the thermostat can regulate engine temperature. Use a laser temp gun and put the red dot on the outflow area and on a black dull surface for good results as you adjust the BLACK knob. Avoid shinny chrome surface due to temp errors. Take your time and do not rush this setting. After you have made this adjustment, you should see ROCK SOLID engine temperature. You will notice speed and motor load will effect your fan RPM - see its working.
By the way, fans with Auto Cool controllers do not KICK ON and off, leave that to the brand X controllers. Please don't tell me your Auto Cool wont KICK on.
FEATURES AND CONTROLS:
Soft Start limits inrush current with pulse width when the controller is powered up. Inrush current is a brand X controller killer when starting a fan motor from a dead stop.
A/C FAN SPEED control has a small pot on the side of the controller. When 12 volts is applied to the A/C controller pin, use a small flat blade screw driver to set this fan speed. The radiator temperature control mode will over ride the A/C fan speed automatically. If not used not a problem.
FAIL SAFE: The fail safe mode turns the fan on full RPM. The FS mode is turned on by grounding the FS pin. Use a small switch from FS to ground. You can turn FS mode on or off any time.
COOL DOWN TIMER: When you turn off the IGNIITION, the fan will keep running for a period of time to cool down your radiator and then shuts down.
FAN BUZZ: The buzz is caused by the fan blade and the armature shaft not tight.
We have found the Mark VIII fan have been reported at no buzz fans.
Our HF-125 controller runs at 7Khz to prevent the buzz but may have a high frequency tone cured by a large filter cap you see below. If your fan is brushless, use our HF controller only. The fan will vibrate at low RPM with low frequency controllers.
START ENGINE: As the motor and radiator is getting warm to hot, the fan will start turning slowly and gain RPM as the temp rises. The RPM will hold at the point of regulation set by the black knob.
Darryl,
I just wanted to let you know that the HF-125 I ordered from you this summer has been absolutely great. As I said, I haul a lot, and big trailers, with my Powerstroke, and now that I'm running your controller, I'm finally getting the benefits of converting it to electric fans. All these years hauling trailers and I've been religious watching temps - I still am, but I can tell you it doesn't matter now if it is 40*f or 100*f, loaded, unloaded, headwind, no wind, 50mph or 80mph, the temperatures are stable all the time. I could not be happier with your controller. In fact, I'm so happy I just ordered a second one for one of my other trucks that I'm converting to electric fans now that I have found the proper way to control them.
Thank you so much for making a quality product.
Joanna Byrne
Lubbock, Texaseasy.
ATTENTION AUTO COOL SHOPPERS:
THE STANDARD BRASS SENSOR IS SOLD WITH ANY CONTROLLER AT NO EXTRA COST. NOT INCLUDED IF YOU PURCHASE ANYOTHER SENSOR. WITH A CONTROLLER.
WE ALSO LOWERED THE PRICE ON THE AUTO COOL 200 LOW FRQUENCY CONTROLLER. ANY QUESTIONS, GIVE US A CALL!
THE STANDARD BRASS SENSOR MOUNTS ON THE OUTFLFOW PORT OF THE RADIATOR UNDER THE RUBBER HOSE. iF YOUR OUTFLOW IS PLASITC DO NOT USE THIS SENSOR. DO NOT MOUNT ON THE RADIATOR INFLOW OR YOUR FAN WILL RUN AT HIGH RPM ALL THE TIME.a
THIS SENSOR IS INCLUDED WITH THE PURCHASE OF A CONTROLLER
AND NOT INCLUDED IF YOU PURCHASE ONE OF THE OTHER SENSORS.
IF YOU HAVE S PLASTIC OUTFLOW PORT, THIS SENSOR WILL NOT WORK.