Hi Daryl molly,
I know this is going to sound dumb, but here goes. Because you mentioned you were camping, were you stationary or traveling when trying the dash heater? The heater works only when traveling and the engine is up to operating temperature. Also, if possible place the air direction on recirculate. Avoid drawing in fresh air. There is no need to bring in fresh air, like a car. The coach has enough ways to allow fresh air into the coach.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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