heater fan never stops

[Mr. Machanic]

It has no A/C.
On start up the heater fan is always running, even with switch in lowest position.
The blower motor resistors show good on the ohm meter.

Is it normal for the fan to always run?

Thanks.

[bd]

Yes.  It reduces the potential for mildew development in the ducts and creates a positive airflow through the cabin to limit exhaust and carbon monoxide accumulation.

[Mr. Machanic]

Thank you.

It is kinda annoying.

[Captkaos]

it should just be running on low, but as bd stated, this is a feature that was added to the trucks in 1973 for crossflow ventilation. You could diconnect the fan power until you don't need it or put it on a toggle, but in the 40 years I have owned these it has never been a big deal to me.

[Rapid Roy]

The low speed wire on the resistor connector can be removed and it will not blow on low. I did this on mine. Instead of a 4 speed fan, I now have 3 speeds and an off position. I have AC on mine.

[Mr. Machanic]

Other than the always on speed, there is only 2 other speeds.
So actually a total of 3 speeds...always on, medium and high.