Quote Originally Posted by gmcbuffalo View Post
Hector
Where is this solenoid located? My Dash heater/AC has a knob that controls it (I think). All the way clockwise there is click and it stops. Turn it CC and it has a large range of motion. The last time I used the coach I didn't notice much differences in the position of this knob. There are two separate knobs for the fans. I forgot to put a manual lever in the engine compartment in the summer mode. The reason I ask where this solenoid is located is I am wondering if I have solenoid or just a manual lever.
GregM
Greg,

The heater solenoid is located behind the front bumper, in the upper portion of the area. I lie on my back in this area and the solenoid is above. My solenoid is hard piped with a copper, with hoses tied in.

In my Country Coach, the knobs that I have appear to be similar to yours. I have two knobs, one that controls the fan speed. The second small knob controls the heat. The electrical diagrams show the knob intergraded with a temperature sensor to control the heat.

I have not checked out the circuitry to see if mine functions as designed, but looks simple enough. I am not sure what actually controls the amount of hot water flow for heat control, but if the solenoid is leaking, hot water will leak through the heater core resulting in a 'warming' of the air you are cooling through the AC evaporator.

Also, my Prevost has two 1/2" block valves in the engine compartment to block the heater hot water, supply and return.

Hector