Setting up an efficient fan setup required fan settings that were also efficient. This took many revisons before I found the perfect configuration but atlas I’ve got it perfect.
This is a sequenced 3 fan setup with fail safes built in. The sequence offers the lowest load impact on the engine keeping a consistent idle. Triggering fans at the same time can cause idle hunting and stumbling that take seconds to stabilize.
Cooling Fans Sequence:
First Fan
The first fan in the sequence is fan 2, witch is a SPAL 12″ pulling fan that is activated by Programable on/off outputs under High Current 2. I have this one turn on at 198f and turn off at 196f. This one alone can keep the engine cool at idle and mild driving conditions.
Second Fan
The second fan in the sequence is fan 1, witch is a SPAL 12″ pulling fan that is activated by Fan Control 203f and off at 195F. When this fan kicks on, Fan 2 has already been on and this additional fan pulls additional electrical load, I increased the idle duty here to compensate for the load and the added rpm increases coolant circulation cooling faster.
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Third Fan
The third fan in the sequence is fan 2, witch is a SPAL 8″ pushing fan in front of the condenser that is activated by Programable on/off outputs under Injector J. I have this fan on at 210f and off at 205f. When this fan kicks on, the others are already on, the idle duty has already been increased. This is considered an auxiliary fan, if it is on the engine is hotter then expected and it offers quicker cooling.
Under normal conditions Cooling Fan 2 is the only one running, the others only run when the engine is working hard or very hot day.
AC Condenser Adaptability:
Fan 2 and Fan 3 both feature a diode from the A/C clutch output that will trigger both fans on when the A/C is turned on. On the radiator Fan 3 is over the condenser and Fan 2 is the opposite side of it on the radiator creating a pushing and pulling air circulation thru the condenser.
Below is my diagram for how the fans are wired ( ALL OEM wiring was bypassed. )
