This may help you repair or understand how your gas heater works.  The MOPAR Instant Gas Heater "Southwind" has five main subassemblies as follows: Burner Blower and Fuel Pump, Heater Assembly, Ventilating Air Blower, Thermostat, and Ignition Unit.  Like a car you need gas, spark and air.  When you first turn the heater switch on, the fuel pump blower assembly pushes air to the burner and at the same time the fuel pump pushes fuel to the burner assembly. (The burner pump INLET is connected at the engine fuel pump OUTLET using a takeoff tee.  Now as you move the temperature lever to HOT, electricity is sent to the thermostat switch causing a solenoid coil assembly to pull on the burner babe assembly unseating it, letting fuel pass into the burner that is ignited by a spark plug located inside the burner assembly.  As the thermostat expanse, electricity is cut off to the coil assembly stopping fuel flow, then as you move the lever to increase heat, the coil turns on again, allowing fuel to flow again.

NOW WHAT TO CHECK FOR IF NOTHING IS WORKING????

1.  Check heater switch while ON (Engine Off -Key On) (While heat lever is off) Wire from battery to switch is HOT - wire from switch to ignition unit is HOT. -wire from ignition unit to blower motor and thermostat switch (both sides) are HOT . And if that is correct then the blower motor is running, the fuel pump is pumping and a (spark plug)  inside the burner is sparking.  Now move the heat lever to warmer and the thermostat switch WHITE wire should not be HOT. The thermostat assembly is factory set but if the need be loosen the set screw in the plastic cam and position it so that the WHITE wire is off just as you move the heat lever to the warmer position and re tight en it.

2.  Check to HEAR if the coil assembly is working (Engine OFF- Key OFF) using a jumper wire from the battery POSITIVE side quickly touch the WHITE wire at the thermostat switch or under the hood wear you see a white and black wire going into the heater box. Touch only the white wire, black is ground; listen for a faint clicking sound (may be hard to hear) that's the coil pulling the valve assembly off its seat allowing fuel to flow to the burner.

3.  Now if these things are OK and working the only thing that may be stopping the gas or spark is that the spark plug gap of .085 is not correct. Or the fuel nozzle and assembly is clogged or dirty, (think of it as a needle and seal similar to a carburetor).  In that case you common sense is all that is needed).

Elroy Braatz Call 530-265-4207 Fax 530-265-2765 Email: braatz@jps.net

Roy would like to get in touch with all owners who have Imperials with gas heaters.  Please send him an email!!!