How the Auto Cool controllers operate:
The sensor measures the OUTFLOW temperature of your radiator
and then sets the fan RPM to regulate the OUTFLOW temperature you have dialed with the black knob. So if you have set the OUTFLOW temperature
10 to 20 degrees F. below your thermostat temperature you will have rock solid engine temperature. Use a laser temperature gun at the OUTFLOW to
check your regulation. Check it parked and motor at an idle.

Also keep in mind, that three things are going to effect the fan RPM.
First is your speed, second is motor loading, and outside air temperature.

Starting your engine for the first time you will NOT see the fans start.
I do not want to hear the BS term "KICKING ON." When the radiator has reached about 140 F, +/-, the fan or fans will start to turn slowly. The fan(s) will increase RPM and reach the point of regulation that you have set with the black knob. For A/C fan speed control, there is a small pot on the side of the controller that sets this fan speed. The radiator control will over ride this fan speed.

Our controllers have Soft Start that limits inrush current from starting a dc fan motor from a dead stop. This is what brand X controller boys fail to realize and why their controllers keep burning out. Auto Cool also has a cool down timer, so when you turn off the ignition, the fans will operate for under a minute.

YOU CAN REACH US VIA THE PHONE OR

EMAIL JUST ABOUT 7 DAYS A WEEK.

DARRYL THE AUTO COOL GUY

562-367-3225

If you return a controller or a sensor for test or repair, please put your full information in the package with name, address, email and phone number!

It will prevent long delays getting it back to you!

The On Line Store Page 1 below. . . .

If you run a brush type fan with the HF-125 and it hums at 7Khz, we can stop the hum with special capacitors.

If you run a brushless fan on a low frequency controller, the fan blade will vibrate at low RPM. Brushless fans should be powered with the
HF-125 controller at 7,000 cycles per second.

If your fan has the buzz, it because the fan blade and the armature is not solid. We find this with the over the counter fans from auto supply companies in general.

The cure is the Buzz Box or go with the HF-125 PWM controller.

Some of the best fans are the Ford Mark VIII fans. Find them at junk yards, Ebay or other parts companies. The Mark VIII have no buzz problem that we have found. The Mark VIII fans can be found in the old Lincolns.

The Mark VIII fans have two speed wires. You will only use the HIGH speed and GROUND wires with any of the Auto Cool Controllers.

The Auto Cool Guy now has these special capacitors to cure the high frequency 7,000 Hz tone in you fan.

One each is included with the purchase of the HF-125 controller.

Be sure to get the polarity correct across the two fan wires. Its sold with the clamp and terminals as you see. Install one per fan only. You will notice that the fan will start to turn very slowly as the radiator is warming up - this is normal.

Use these caps only with the HF-125 controller if your fan has the high frequency tone problem.

Hi good morning Darryl The Auto Cool Guy, from the Philippines Islands. Here is my HF-125 up and running smoothly on my 2000 LN166 Toyota Hilux 1kz-te diesel engine with rear mounted radiator beats that heat in the PI!

Best regards, nelbin binag

DIESEL RADIATOR TEMPERATURE CONTROL

I made this video of the DX-150 - how it works on the bench.

Sensor Warning: If your radiator OUTFLOW port is plastic, do not use the Standard Brass sensor. It will not get true heat transferred to the sensor! This will result in very low or no fan RPM.

US ARMY ORDINANCE:
CALLED UP FOR A TOUR IN SOUTH EAST ASIA AND ASSIGNED TO THE 295TH ORD. FROM HASTINGS & GRAND ISLAND, NEBRASKA
10-68 TO 10-69.

The photo on the left is the Auto Cool Guy. Location was north of Quan Tri City just south of the DMZ. When we were out of our base camp we always carried our M16s and at least 8 clips of .223 ammo with 20 rounds in each clip.

The photo on the right was taken one night outside of our hooch in Da Nang. For some reason I loaded 35mm high speed slide film in my camera and had it mounted on a tripod ready to go that night. As we were drinking beer and such, all hell brook loose and the sirens went off. Then we heard one of our NCOs telling us to get into our bunker. We answered back to this NCO that we were busy drinking and taking war photos. With my camera and standard lens I shot this time laps photo of a Cobra gun shop spraying 7.62mm rounds on the Da Nang perimeter. In the morning all the MPs found was a dead water buffalo. So you see all the fun you can have in the Army!

We have been building pulse width modulated radiator temperature controllers right here in the USA starting in 2011. We design and build quality and what the customers want!

The Auto Cool Guy supplies the Standard Brass Sensor with your controller. However, if you purchase a Brass Plug Sensor or one of the Copper Inline Sensors, we do not supply the Standard Brass Sensor as the default sensor with your order.

Attention Australian buyers: The cost to ship controllers to your country has gone way up! Fed-X will be the system used from now on. We will get a shipping cost and email you the added expense. There may also be a delay in Pay Pal payments to us. What a bloody mess!

The HF-125 is our new high frequency controller that operates at 7,000 Hz. This is the controller you want if you are going to power a BRUSHLESS fan motor. It will also power any brush type motor. It will prevent fan BUZZ ound in some Asian fans.

However, the HF-125 may have a "TONE" with some fans. So we will include a filter capacitor to install across your fan if you discover this problem. If you have two fans, you will need to order a second filter fapacitor from our on line store.

The BUZZ is caused by the fan and the amature not being tight

and shows up with low frequency controllers. It will be real loud at low fan RPM.

Our HF-125 has soft start and the cool down timer. . Two large 1/4 inch brass studs for fan and ground power. The top and bottom of the HF-125 is made from 1/8 inch aluminum plate for a heavy duty heat sink. The top case in powder coated.

HF-125 7 KHz PWM CONTROLLER

$265.00

HF-125 7 KHz PWM CONTROLLER

See our return policy data sheet