Fresh Air and Air Flow were the names used for the heat-control-valve "deluxe" heaters between 47-55. From 53-55 these heaters were truly "Fresh Air" heaters, in that they had a control cable to let fresh outside air pass through the heater core (defrost was controlled by a lever similar to the lever on a Recirculating Heater). From 47-52, the control cable controlled defrost vs downward/floor heat.
I had mentioned in a past Post that if you took the front cover and door portion of the 53-55 "Fresh Air" heater.
And put it on the front of the 47-52 Air Flow heater.
You would kinda have a hybrid heater with 2 control cables.
The 47-52 Air Flow heater control cable, directs ether defrost or floor air.
The 53-55 "Fresh Air" heater control cable, controls whether it recirculates Cab air or brings in fresh air.
I'm almost 100% positive the 2 front covers have the same footprint.
Put
this front cover pic 1 &
pic 2 on the body of
this heater. You would have to slightly modify the control cable attaching post to accommodate 2 cables.
Then find a spot to mount the 2nd cable knob, next to the original knob.
Hey, Deve nice mod on the Heater switch.
Resistors in the air flow.
http://devestechnet.com/Home/Native12VUpgrade#heatersystem I had a hard time finding the link from your home page.
