Heater Issue Resolved
 

After many camping trips with the heater working sporadically, it's fixed!!!

The symptoms where;

Not always igniting the furnace burner when I had spark ignition (the spark clicking noise)and it was the only appliance on, burner on furnace going out when another appliance was turned on, yellow flame on stove burner.

Low Gas Pressure = Replaced Propane Gas Regulator at Propane Tanks

The regulator on my trailer was 13 years old, the pressure diaphragm wears out in 8 to 10 years.

Cost of Gas Regulator $50.00