[Monkey Wrench]

in volvos of the same era it is common to install a heater fan with more windings and an updated switch. It'll then use winding 1 , 2 or both to change speeds.

it sounds like Porsche only used a 1 speed motor in the 944 ( rad fan not heater blower motor) but perhaps later models or updates could use a motor with more choices of field windings rather than adding power wasting resistors in series to slow the motor which is essentially electrically inefficient. .

the 1 speed motor might be slowed by switching in a resistor in series.. power after the resistor will be less than 12V due to the power drop through the resistor so the slower speed is the motor basically running at less than 12V .


a motor with more windings may not need a resistor to change speeds , they may use 1 2 or both windings to get the three speeds and then no resistor is needed.

I think that similar to the rad , the resistor is basically a very inefficient device, it's sole purpose in life is to waste energy. Perhaps it is possible to upgrade a fan motor if the amp draw is of particular concern.

Best advice is probably to follow Clark's garage notes and keep it OEM.

Liverpool has similar weather to BC. Its not like the southern US, I wonder if Porsche realized that colder climates dont need AC or that extra fan.. perhaps that meant different options from the factory by region?

adding or deleting AC may have never been a dealer task, they were probably only sold as built in the factory.

I did not notice an option code on mine for AC.