51
17. FAULT CODES
When the boiler detects a temporary fault condition, the
appropriate code is shown flashing on the display. If/when the
fault code is final, the pump will perform a 60-second post
circulation and the red LED will be illuminated.
CODE CAUSE ALARM TYPE ACTION
AL10 Ignition failure/not flame sensed, Final Reset, check appliance operation
condense sensor activated
AL20 Limit thermostat fault, blocked flue switch,
flue thermostat Final Reset, check appliance operation
AL21 External device fault (UHT/CPA) Final Reset, check appliance
AL26 Return temperature too high Final Reset, check pump, ensure there is sufficient
flow sensor temperature). Circulation around
heating circuit/s
AL28 Temperature differential inverted Final Reset, check pump, ensure there is sufficient
(return sensor temperature higher than circulation around heating circuit/s thermistors
flowsensor temperature)
AL29 Flue sensor over temperature lock out Final Reset check appliance operation
AL34 Fan blower signal fault Final Reset check appliance operation, check fan
AL40 Insufficient system water pressure Final Check/refill system pressure, reset, check
appliance operation
AL41 Insufficient system water pressure Temporary Check/refill system pressure, check appliance
operation
AL52 Internal fault Final Reset, check boiler operation
AL55 Jumper tag fault Final Check jumper tag configuration
AL60 Jumper tag fault Temporary Check jumper tag configuration
AL71 Primary (flow) sensor fault Temporary Check primary thermistor, check wiring
AL73 Return sensor fault Temporary Check return thermistor, check /wiring
AL74 Variation on temperature of primary Final Reset, check boiler operation, check
and/or return too high pump, ensure there is
sufficient circulation around heating circuit/s
AL79 Flow temperature too high, or Final Reset, check appliance operation, check
temperature differential between thermistors
primary and return too high
AL91 The main heat exchanger need to be Advice Call the Raypak technical service
cleaned