Stock Heater Options

[blown240]

I plan on putting AC in my Panel, but I wanted to see what the difference is between some parts I have.

Right now my truck has this heater:

The blower works, but its weak, and I'm missing the ducting for defrost.





I have this in my spare parts:

I was told that this was for trucks with A/C, but I don't see any AC lines going into it. I am missing all the interior parts.






I also have this. Its heat and AC, and R134. But its really tiny, and probably won't cool a panel truck very well.







I was thinking of making a new face plate for the newer unit, and mounting it like an under dash unit. It would at least blow cold air, even if it never really cooled too well...

Thoughts?

[AcampoDave]

The heater in your truck is a recirculating heater. Mostly used up until '63. As the name implies, it simply uses interior air to do its job which makes for a poor defroster. The second one is a fresh air heater. It mounts on the underhood side of the firewall where your truck currently utilizes a pair of block off plates. It draws air from the cowl providing a better defrost and forced air when the truck is in motion. The deluxe version had a trap door inside used to regulate airflow thru or around the core allowing for temperature control. Looks like yours may have that option as I believe I see a lever on the side by the air intake. As for the third one, I'm not of much help. Edit: When airflow becomes weak on the recirculating version its usually because the core is all coated with hair, lint, and crappola and the fan can't draw thru it very well.

[Slow Build]

That under hood heater is not an AC unit .

[OldGMJon]

Originally Posted by Slow Build

That under hood heater is not an AC unit .

This is an under hood A/C heater box and core. The center air flap allows fresh air from the cowl area to bypass the heater core and enter the cab. The dash's backside needs to be cut between the mounting bolts to accommodate. There is a template for that on one of these threads. The under dash A/C component takes the place of the under dash heater box and directs both the cooling and heating air. From a 66' GMC 2503...

[blown240]

Thanks for the replies. I'll check to see if the core is blocked in the unit that a in there now, and I'll try to get the newer one setup...

[Captainfab]

The Deluxe heater you have is the '64-5-6 version. I'm not sure just what is needed to bolt it up to a '60-'63 and make it work. I've always just used the correct one.

[blown240]

Thanks for posting that! That filled in a lot of the gaps in my information!!