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Problem
Probable Cause
Solution
Steady On-No
Operation
Internal control fault
One Flash:
Combustion
Airflow Fault
Faulty combustion blower
Check for 230V supply and tightness at fan
connections If no power, replace
Airflow switch not closing
Check for 230V supply and tightness at fan
connections If no power, replace
Airflow switch opened during operation
Two Flash:
Flame with No
Call for Heat
Faulty gas valve
Check voltage to gas valve with thermostat
off, valve should not be powered, if there is
gas flow, replace valve
Three Flash:
Ignition Lockout
Ignition control miscommunication
Reset ignition control by removing 24V
power to ignition control terminal 24VAC
Dirty burners
Clean burners to ensure proper
flame carryover
Faulty spark igniter
Check if connecting lead or spark igniter are
damaged, if yes, replace
Faulty flame sensor
Check if connecting lead or flame probe
are damaged and/or touching earthed
components, if yes, replace
Incorrect gas pressure at gas valve
Check gas pressure at inlet of valve is
correct for gas type, if no, correct
pressure problem
Faulty gas valve
Check gas pressure at outlet of the valve
rises when valve turns on and returns to
zero or lower when valve turns off,
if no, replace
Table 13.6: Gas Furnace
LED flashes on for 1/4 second and off for 1/4 second during fault condition. Pause between fault codes is 3 seconds.
PR Series Installation, Operation, and Maintenance Manual
