Lochinvar GAS HEATER FOR COMMERICAL POOL APPLICATIONS Hot Surface Ignition Control Module

Commercial Pool Heaters

OPERATION Continued

HOT SURFACE IGNITION SYSTEM

Hot Surface Igniter and Ignition Control Module

This unit has one ignition module and one hot surface igniter.

￿CAUTION: The igniter is extremely fragile, be very careful when removing. A faulty or damaged hot surface igniter MUST BE replaced with a Lochinvar PLT3400 igniter. DO NOT use general purpose field replacement igniters.

Figure 47 – Hot Surface Igniter

Figure 48 – Hot Surface Ignition Control Module

Hot Surface Ignition Control Module

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 after an approximate five-minute waiting period. This soft-lockout condition is intended to allow self-correcting faults to correct themselves and permit normal operation. A typical hard- lockout fault is a flame failure condition. An ignition module that is in a hard-lockout condition may only be reset by pushing the reset button for the ignition control. The reset button is located on the front of the control panel. Upon a flame failure, the reset button is only active after the control module has completed its post-purge cycle. Turning 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 fans for the post purge cycle and then the ignition module will pause for approximately five minutes. 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 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 thermostat or turning the main power switch “OFF” and then “ON” after the control sensed fault has been corrected.

Diagnostic Status Indication

The ignition module has an LED which indicates the status of the safety circuits. A remote Ignition Module Status indicating light is wired from the ignition module Status LED and mounted on the front control panel. The flashing operation of this light/LED indicates the diagnostic status of the ignition control module. The status LED, mounted on the ignition module, flashes a code sequence from the Ignition Module to indicate the status of the ignition process. See TABLE– N, on page 43 for the flashing diagnostic status codes as signaled by the ignition module.

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