Lochinvar EW150 Installation & Service Manual page 46

8
Troubleshooting
STEP
IGNITER / SENSOR WARMS UP
9
AND GLOWS RED.
YES
STEP
IGNITION MODULE VALVE
10
"LED" LIGHTS UP?
YES
STEP
IGNITER "LED" TURNS OFF
11
& VALVE "LED" STAYS ON?
CHASSIS GROUND & WIRING CONNECTIONS TO IGNITER?
YES
STEP
MAIN BURNER RUNS UNTIL
12
CALL FOR HEAT ENDS AND
VALVE "LED" TURNS OFF?
YES
STEP
SET THERMOSTAT ABOVE
13
WATER TEMPERATURE?
YES
STEP
THERMOSTAT OPENS?
14
YES
STEP
GAS VALVE CLOSES?
15
YES
STEP
CAB STOPS AFTER 30 SEC. POST PURGE?
16
YES
STEP
SYSTEM OK?
17
46
TROUBLESHOOTING CHART
120 VAC AT IGNITER/SENSOR?
NO
REPLACE IGNITER/SENSOR.
"LED" BURNED OUT BUT CONTROL
NO
FUNCTIONS. REPLACE AT A
CONVENIENT TIME.
24 VAC TO GAS VALVE?
NO
GAS VALVE OPEN?
IGNITER/SENSOR MOUNT PROPERLY?
GAS SUPPLY PRESSURE TO GAS VALVE CORRECT?
MANIFOLD PRESSURE CORRECT?
NO
REPLACE IGNITER.
CONTINUITY OF CHASSIS
GROUND CONNECTIONS?
IGNITER/SENSOR MOUNTED PROPERLY?
NO
REPLACE IGNITER.
NO
GAS VALVE CLOSES WHEN ONE LEAD IS REMOVED?
REPEAT PROCEDURE UNTIL
NO
SYSTEM OPERATES NORMALLY.
Installation & Service Manual
NO
YES
CHECK WIRING CONNECTIONS.
NO
YES
REPLACE GAS VALVE.
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
TIGHTEN OR REPLACE GROUND.
NO
YES
NO
YES
CHECK WIRING CONNECTIONS.
NO
REPLACE MODULE.
CHECK WIRING CONNECTIONS.
CHECK MOUNTING.
SET GAS SUPPLY PRESSURE.
SEE INSTRUCTIONS.
SET MANIFOLD PRESSURE.
SEE INSTRUCTIONS.
CORRECT MOUNTING.
REPLACE THERMOSTAT.
REPLACE GAS VALVE.