Page 36
13369-1-0203
Note: Before troubleshooting, familarize yourself with the startup
and checkout procedure.
Check line voltage power, low voltage transformer, limit
control, thermostat and wiring.
Pull ignition lead
and check spark at
ignition stud.
Spark okay?
Replace module.
N o
• Check that all manual gas valves are open. Supply tubing
and pressures are good, and pilot burner orifice is not blocked.
• Check electrical connections between module and pilot
operator on gas control.
• Check for 24 VAC across PV — MV/PV terminals on module.
If voltage is okay, replace gas control. If not, replace module.
•Note: If S8600H goes into lockout, reset system.
• Check continuity of ignition cable and ground wire.
• Check that pilot flame covers electrode.
• Adjust pilot flame current. Minimum signal should read 1.0
microamp.
• If problem persists, replace module.
• Check ignition cable, ground wiring, 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 excessive temperatures.
• Check for 24 VAC across MV-MV/PV terminals. If no voltage,
replace module.
• Check electrical connections between module and gas control.
If okay, replace gas control.
Note: If S8600H goes into lockout, reset system.
• 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.
• If checks are okay, replace module.
• Check for proper thermostat operation.
• Remove MV lead at module: If valve closes, recheck
thermostat and wiring. If not, replace gas control.
N o
N o
N o
N o
N o
N o
N o
Repeat procedure until troublefree operation is obtained.
Yes
Yes
Yes
Yes
Yes
Yes
Yes
START
Turn gas supply off.
Turn thermostat
to call for heat.
Spark stops when
pilot is lit?
Power to module.
(24 VAC nominal)
Spark across
Igniter/sensor gap.
Turn gas supply on.
Pilot burner lights?
Main burner lights?
System runs until
call for heat ends?
Call for heat ends.
System shuts off?
Troubleshooting ends.
Yes
S8600H TROUBLESHOOTING GUIDE
DVS-36 & DVS-42 INTERMITTENT PILOT TROUBLESHOOTING (continued)
