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A-1. Intermittent Pilot
Ignition System Checks
STEP 1: Check ignition cable.
a. Verify ignition cable does not make contact with
metal surfaces.
b. Verify only factory supplied Ignition cable (or
approved replacement) is used.
c. Verify connections to ignition module and igniter or
igniter-sensor are clean and tight.
d. Verify ignition cable provides good electrical
continuity.
STEP 2:
Verify ignition system grounding. Nuisance shutdowns are
often caused by poor or erratic grounding.
Common ground is required for module and pilot burner/
igniter sensor.
‒
Check for good metal-to-metal contact between pilot
burner bracket and the main burner.
‒
Check ground lead from GND (BURNER) terminal
on module to pilot burner. Verify connections are
clean and tight. If wire is damaged or deteriorated,
replace with No. 14-18 gauge, moisture-resistant,
thermoplastic insulated wire with 105°C [221°F]
minimum rating.
‒ Check ceramic flame rod insulator for cracks or
evidence of exposure to extreme heat, which can
permit leakage to ground. Replace pilot burner/
igniter sensor and provide shield if necessary.
‒ If flame rod or bracket is bent out of position,
restore to correct position.
If this LED is blinking and the burner is not firing:
Make sure the plug connection (or jumper, on boilers where
vent damper plug is not used) is secure.
Make sure the plug connection at the vent damper end is
secure and oriented correctly.
Make sure damper motor turns.
Verify the damper end switch has closed
DANGER
Carbon Monoxide Hazard:
If the burner fires
when the vent damper is not fully opened or there is
any other blockage in the flue, dangerous flue
products, such as carbon monoxide, will escape into
the living space causing severe personal injury or
death. The flue as well as the vent damper must be
checked for proper operation before allowing the
system to operate.
!
Circ Delay LED
The blue “circ delay” LED lights to indicate the heating
circulator (terminal C1) is being held off.
To minimize condensation on the boiler heat exchanger
and in the flue due to low water temperature, the
circulator is not energized until the boiler water
temperature reaches 125°F.
At that point, the circulator will be powered on and the
LED will turn off.
If the boiler water temperature falls below 115°F the
circulator will turn off again and the LED will illuminate
until the temperature reaches 125°F again.
9
APPENDIX A - CONTROL FUNCTION
PN 240012785 Rev. C [11/15/2020]
