HOT SURFACE IGNITION SYSTEM
IGNITION CONTROL MODULE
DIAGNOSTIC STATUS CODES |
FIG. 63 Hot Surface Ignition Control Module
This appliance uses a proven hot surface ignition control system. The operation of the electronic control module for the hot surface igniter proves the presence of an ignition source much like a proven standing pilot before the gas valves are energized. The ignition control module starts and proves the operation of the combustion air blower, proves the presence of the proper ignition temperatures from the hot surface igniter, energizes the main gas valves, proves the presence of main burner flame, provides for soft lockouts on control sensed faults, provides a hard lockout on flame failure and controls the pre and post purge timings of the combustion air blower. A status point alarm of FlameFail will be displayed in the Command Display on a hard lockout for flame failure.
Service Parts
This appliance uses a proven electronic ignition control module and a hot surface igniter. The electronic ignition module is not repairable. Any modification or repairs will invalidate the warranty and may create hazardous conditions that result in property damage, personal injury, fire, explosion and/or toxic gases. A faulty hot surface igniter or ignition module MUST be replaced with a new
OEM unit only. An OEM specification igniter and ignition control module for this specific unit is available from your local distributor. DO NOT use general purpose field replacement ignition modules or igniters. Each appliance has one ignition module and one hot surface igniter.
Ignition Module Lockout Functions
The ignition module may lockout in either a hard lockout condition requiring pushing of the reset button to recycle the control or a soft lockout condition which may recycle in a fixed time period to check for correction of the fault condition. A typical hard lockout fault is a flame failure condition. Pushing the reset button for the ignition control is the only way to reset an ignition module that is in a hard lockout condition. The reset button is located on the inside front control panel. The reset button is active after the post purge cycle when there is a hard lockout condition as indicated by the Status LED. Turning the main power “OFF” and then “ON” or cycling the thermostat will not reset a hard lockout condition. Wait five seconds after turning on the main power before pushing the reset button when the ignition module is in a hard lockout. The ignition module will go into a soft lockout in conditions of low air, low voltage or low hot surface igniter current. A soft lockout condition will operate the combustion air blower for the post purge cycle and then the ignition module will pause for a fixed time period. The timed length of the pause is based on the type of fault sensed by the control module. At the end of this timed pause, the ignition module will attempt a new trial for ignition sequence. If the soft lockout fault condition has subsided or has been corrected at the end of the timed pause, main burner ignition should be achieved with the resumption of the normal trial for ignition sequence. If the control sensed fault is not corrected, the ignition module will continue in the soft lockout condition. If the electronic thermostat opens during the soft lockout period, the ignition module will exit soft lockout and wait for a new call for heat from the thermostat. A soft lockout condition may also be reset by manually cycling the electronic thermostat or turning the main power switch “OFF” and then “ON” after the control sensed fault has been corrected. SoftLockout will be shown in the screen of the Command Display when the ignition control module has gone into a soft lockout condition.
FIG. 64 Hot Surface Igniter
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