I am installing a heater in the box of my straight truck. It is a 2002 International 4300 with a 466e. The heater is just a heater core and blower that will use engine coolant for the heat source.
I'm not sure if I should plumb it in parallel or series with the cab heater core. Anybody know if the coolant flows full through the cab heater core all the time or is there some sort of a heat control valve in there?
Thanks,
JP.