hi guys, my heater puts out heat even though it's not turned on. that's not so bad now that it's cool outside but it won't be any fun during the summer. it's not that the blower is running but that the heater hoses and the carcass of the heater are hot and the heat flows into the cab. could i correct that problem by putting a manual valve on one of the hoses inside the engine compartment. during the summer i could close the valve and wouldn't that prevent the hot water from entering the heater box and heat from entering the cab. does anyone foresee a problem doing this? thank you. PS, i'm working on a 1950 1/2 ton. heater appears to be original; not sure what kind it is.
