Trouble Shooting Table - Garland 200 Service Manual

TROUBLE SHOOTING TABLE

START
TURN GAS SUPPLY OFF.
TURN CONTROLLER TO
CALL FOR HEAT POWER
TO MODULE
(24V NOMINAL)
YES
SPARK ACROSS IGNITER/
SENSOR GAP
YES
TURN GAS SUPPLY ON
PILOT BURNER LIGHTS?
YES
SPARK STOPS WHEN
PILOT IS LIT?
YES
MAIN BURNER LIGHTS?
YES
SYSTEM RUNS UNTIL
CALL FOR HEAT LOSS?
YES
CALL FOR HEAT ENDS
SYSTEM SHUTS OFF?
YES
TROUBLE SHOOTING
ENDS
Part # MCOSM06 Rev 1 (11/03/08)
NO
Check line voltage power, low voltage transformer, limit controlled and wiring.
Pull ignition lead
and check spark and
module.
NO
Spark okay?
YES
• Check ignition cable, ground wire, ceramic insulator and gap and correct.
• Check boot of the ignition cable for signs of melting or buckling. Take protective action to shield
cable and boot from excess temperature.
• Check that all manual gas valves are open, supply tubing and pressure are good, and pilot burner
orifice is not blocked.
• Check electric connections between module and pilot operator on gas control.
NO
• Check for 24 VAC across PV-MV/PV terminals on module. If voltage is okay, replace gas control; if
not, replace module.
Note: If S5800B, H; S6810B, H goes into lockout, reset system. For S6800M, wait 6 minutes nominal
for retry or reset system
• Check continuity of ignition cable to ground wire.
• Clean flame rod.
NO
• Check electrical connection between flame rod and module.
• Check for cracked ceramic flame rod insulator.
• Check that the pilot flame covers the road and is steady and blue.
• Adjust pilot flame.
• If problem persists, replace module.
• Check for 24 VAC across MV-MV\PV terminals. If no voltage, replace module.
NO
• Check electrical connections between module and gas control. If okay, replace gas control or gas
control operator.
Note: If S8600B, H; S6810B, H goes into lockout, reset system. For S6800M, wait 6 minutes, nominally
for retry or reset system.
NO
• Check continuity of ignition cable and ground wire.
Note. If ground is poor or erratic, shutdowns may occur occasionally even though operation is
normal at the time of checkout.
• Check that the pilot flame covers flame rod and is steady and blue.
• If checks are okay, replace the module.
NO
• Check for proper controller operation
• Remove MV lead at module; if valve closes, recheck the temperature controller and wiring; if not,
replace gas control.
Repeat procedure until trouble free operation is obtained.
Note: Before trouble shooting familiarize yourself with
the startup procedure.
• On models with vent damper plug, make sure vent damper
had not be installed, the remove. Replace vent damper if
NO
necessary.
• On other models, replace module
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