[gdirwin]

I have a liquid cooled Zilla - the pump (VW aux cooling pump) always runs, and pushes coolant through a small radiator. The radiator has a small fan on it (12V) - I want this fan to only come on when the coolant is above a certain temperature (say 30 deg C).

Can anyone suggest a fluid thermal sensor/contact which will do this?

This seems to be an odd-ball item - I know some computer cooling systems include such items, but other than that it seems hard to find...

Thanks!

 

[gdirwin]

I thought of using the ICE's engine coolant temperature sensor - this would get the stock gauge to show the coolant temperature. I could also use the OEM fan output (which turned on the bug 12V fans for the OEM radiator)...

Unfortunately I wanted the dash temperature gauge to show me the motor temperature (not the controller coolant temperature).

Anyone have ideas? Cannot seem to find an inline temperature contact/switch which will turn on a fan above 30 deg C...

 

[Roy Von Rogers]

If your looking for something to control the fan, go to any major auto store that sells radiator cooling fans, they have a 12v thermostat that has an adustable shaft.

I have one on my E250 and it works like a charm, have had it for years.

Roy

I thought of using the ICE's engine coolant temperature sensor - this would get the stock gauge to show the coolant temperature. I could also use the OEM fan output (which turned on the bug 12V fans for the OEM radiator)...

Unfortunately I wanted the dash temperature gauge to show me the motor temperature (not the controller coolant temperature).

Anyone have ideas? Cannot seem to find an inline temperature contact/switch which will turn on a fan above 30 deg C...

 

[gdirwin]

Thanks Roy - this is a good idea and gives me more places to look. The thermostats for ICEs seem to all turn on at around 160F to 180F (70C to 80C) - this is too hot for power electronic controllers. The Zilla will throttle back for anything above 130F (55C).

Ideally it would be an inline sensor (2nd choice is a bulb style), adjustable down to 20C or so... I would probably set it to turn on the fan if the coolant is above 25C, and to turn off if it is below 20C.

I will keep looking for an adjustable 12V thermostat/switch - I thought of sensors for water-bed heaters, so will check into this too...