Advanced Products

Model: OK6

OK6 Hydraulic Oil Cooler

The OK6 provides up to 200,000 Btu/h of heat rejection. This unit is perfect for any oil or glycol cooling needs in applications with high cooling demand. Some applications include electronics cooling for large articulated hybrid transit busses, hydraulics oil cooling for large farm, forestry, construction, and mining equipment, and primary engine cooling for medium sized vehicles and equipment. The OK6 features six variable-speed EMP fans with long-life brushless motors and full reversibility to keep the heat exchanger clean through years of harsh use.

The OK6 is available in 12V and 24V, pusher and puller models. Control strategy can be configured as temperature control, PWM or CAN control, or simple on/off. Temperature controlled OK6 models feature an EMP uTMC system controller. Custom fan layouts are available upon request.

Front View
OK6 Chart
Install View
Install View

Features & Benefits

EMP Brushless Electric Fan

All OK6 coolers feature EMP fans. EMP's fans are brushless, controllable, reversible, and built from a cast aluminum shroud that can withstand even the harshest environments.


Type Specification Description
Max Heat Rejection Rate 200,000 Btu/h
Overall Package Weight (Without Fluid) 275 lbs.
Heat Exchanger Material Aluminum
Shroud Material Steel
Max Continuous Operating Temp 203° F
Min Continuous Operating Temp -40° F
Max Fluid Temp 212° F
Fan Configuration Push or Pull
Voltage 12 or 24 Volts
Max Current 150 Amps
Max Power Varies by Design
Max Fan Speed 4000 RPM (14V)
4600 RPM (28V)
Max Continuous Operating Pressure 220 psi
SAE O-Ring Boss Port Size -16 (1 5/16" - 12)
Maximum Fluid Flow Rate 22.5 GPM
Heat Exchanger Fluid Volume 4.5 Gal.
Control Inputs On/Off, CAN/J1939, PWM or Thermistor
Fan Reversal Control Push Button, Timed, or Ignition On


Please click on the thumbnail below to view a larger version of the image.


The following kit options are available for this product. Any combination of options below can be choosen to configure the kit to your needs.

Voltage Configuration
12V 24V Push Pull
Optional Approval Rating
UL-Approved CSA-Approved
On/Off PWM J1939 CAN Thermistor EMP-Link


Hybrid Transit Bus

OK6 Electronics Cooling for Hybrid Transit Bus

Downloads & Documents

The following documents are available for this product. Please feel free to download to obtain additional product information.