Variable Current Controllers for Electric Cooling
Fans
In this Article, Michael Yount describes the installation of his new
Variable Speed Fan controller in his hybrid 82 Volvo.
Since adding performance upgrades to the 5.0L Ford V-8 in my 82 242
Volvo, I’ve looked for ways to assure the integrity of the cooling
system. I installed a contemporary 3-row, 18 fin/inch core in the radiator,
along with a fully shrouded dual 11” SPAL electric cooling fan
set up. So there is plenty of cooling capacity as well as plenty of
air movement to keep things cool. However, there are many different
options for controlling the cooling fans. Originally I chose to control
the two fans separately with relays and separate temperature switches.
One switch operated with a 195F fan on, 180F fan off; the second kicked
in if temps rose to 210F, and turned off at 195F. It worked well during
the summer with a 170F thermostat, but as winter rolled around, the
170F thermostat proved a little too chilly for the engine, and I noticed
a slight degrade in fuel mileage. So I began to explore how to control
the fans more effectively with a higher temperature thermostat.
