[77newell]

I'm about to charge mindlessly into the heating and defroster system in the front of my 93 coach and I have a couple question.

My heater barely keeps up when outdoor temps are in the high 40's. Assuming other similar coaches have similar heater systems, has anyone traveled in colder temps and survived? I'm trying to assess if the system is operating correctly but is inadequately sized or if it is just not functioning properly.

Question 2; where is the modulating valve that controls the flow rate of coolant to the heater core? It is operated by wire from the lever on the dash panel.

Any insight is gratefully accepted.