heater fan - always on?

[SirRobyn0]

@SirRobyn0

To repeat what has already been stated, early squares without AC, the fan always runs. Not many differences between the 73's and 74's. My 1974 Jimmy I bought new in 1974, the blower was on with the key. No off for the fan.

I'm sorry somehow or another I missed that or it didn't sink in properly. I have not seen a 73 or 74 recently so that would likely be why I don't remember that. Thanks for correcting me.

 

[Ellie Niner]

Yep. My non A/C 1975 GMC operates like this. Sliding the HEAT/DEF lever to OFF just redirects airflow to a port in the heater box that blows it upward under the dashboard; blower keeps running at whatever speed you have it set at.

I always thought this was a carryover from the "Astro Ventilation" days, which was what GM dubbed their flow-thru ventilation system after they took the wing windows away on cars circa-1968.