Shutting Off The Heat In A Cabbed Tractor

[Ductape]

I've noticed when I am running my A/C in the summer, I can still feel a little warm air coming out of the defroster vants over the windshield. Though the A/C still makes it comfortable in the cab, I'm thinking the A/C would be more efficient (cooler) if I stopped the coolant from circulating through the heater core in the summer. The simplest solution I see is to install a ball valve in one of the heater hoses... possibly right at the nipple the hose slips over. Anyone have thoughts on this? Am i on the wrong track?

 

[DK35vince]

I think you are on the right track.
A valve on the heater hoses should work fine.

 

[WM75Guy]

We had those on ambulances for years. A simple inline valve on the supply side. Turned it off in the spring, back on in the fall. Made a big difference in the patient compartment during the summer with the AC not competing with the heater core.

 

[mpham]

Check under the hood where the heater hose connects to the engine. Mine already has a shutoff there.

 

[RickB]

Whether the shutoff is in the supply or return side is immaterial. Stopping the flow is key. When the heater and A/C get fighting, the heater wins every time!