Auxiliary heater - activate ventilation EXTRA

Hello,


The Webasto Thermo Top is now finally installed. I'm now looking for a circuit that only turns on the ventilation system, which normally runs constantly and puts a strain on the battery, once the water has already reached a certain temperature (perhaps 40-50°?).
I haven't found a suitable temperature switch yet, and I don't want to use a bimetallic switch. It's too fussy for me.
I was already thinking about a circuit that, depending on the outside temperature, proportionally increases the fan speed (a power switch from the model airplane hobby...).

Has anyone tried this idea or something similar before?

Stefan.

Um...

My Thermo Top only activates the vehicle fan when the coolant reaches 30°C. Are you sure everything is wired correctly?

CU Gremlin.

hello,


My heater used to be a supplementary heater. I've also tried connecting the cable that outputs the temperature signal, just for testing purposes. However, no signal is received .

Now I'm looking for an alternative.


Stefan.

Hello,

Just use a simple timer that turns on the fan after about 5 minutes. It can be easily built using an NE555 timer chip.
I control the speed of my fan continuously using a potentiometer with a PWM circuit. Here, you could also use a cheap NTC temperature sensor (e.g., from www.pollin.de) to control the fan...


Regards,
Lucas.