TM 5-4520-253-13
Table 3-3. Unit Maintenance Troubleshooting – Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Death or serious injury could occur if pre-
cautions are not taken when maintaining this
equipment. Be sure that any power cables
are unplugged/disconnected. Be sure that the
equipment is properly grounded. Always have
another person standing by who is trained in
electric shock first aid.
Step 3. Check room thermostat cable. With cable plugged into ROOM THERMO
receptacle, remove cover from room thermostat, turn temperature adjustment
knob to high setting, place HEATER-OFF-FAN switch in HEATER position,
and check for 120 V ac across thermostat switch terminals.
No voltage at
thermostat switch terminals indicates defective cable or plug. Check plug for
loose connections or damage. Check cable wires for continuity.
To replace defective room thermostat plug, refer to REMOVE/lNSTALL
POWER, FUEL PUMP, AND ROOM THERMOSTAT PLUGS, page 3-124.
To replace defective room thermostat cable, refer also to page 3-121.
3. HEATER STARTS, THEN STOPS. RED FAULT LIGHT COMES ON.
Death or serious injury could occur if fuel is
not handled carefully. Use in a well-ventilated
area away from open flame, arcing equipment,
ignition sources, heaters, or excessive heat.
Engines must be turned off and cool before
refueling. Use proper refueling procedures
and equipment to avoid spillage. Do not run
engines near open fuel containers. Do not use
fuel as a cleaning solvent. DO NOT SMOKE.
Step 1. Check for low fuel supply.
Replenish fuel supply.
Step 2. Check fuel shutoff valve.
Be sure fuel shutoff valve is completely open during operation.
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