Baxi · Error codes
Baxi error codes and alerts
Identical code numbers can mean different things on different controllers, so every entry is tied to the documented series, controller and manual version. A code is never a diagnosis.
If you smell gas
- Stop what you are doing. Do not use phones, switches, matches or anything that can spark inside.
- Go outside and leave the door open behind you.
- Call the FortisBC 24-hour emergency line at 1-800-663-9911 or dial 911.
Only after that, call ROMA about the boiler. Official guidance: FortisBC gas leaks and odour.
Baxi Luna Duo-tec GA combi boilers (fault codes, I&O 7703472.01; 60GA/1.48GA in 240012485)
09
Gas valve connection fault. Check cable PCB/gas valve and gas valve plug. The table classifies it as Lockout (manual reset).…
Lockout
10
Outdoor sensor fault. Check sensor and cable. The table classifies it as Lockout (manual reset).…
Lockout
15
Gas valve command fault. Verify all cables. Replace PCB. Call authorized SERVICE center. The table classifies it as Lockout (manual reset).…
Lockout
20
Central Heating NTC sensor fault. Check sensor and cable. The table classifies it as Lockout (manual reset).…
Lockout
28
Flue NTC heat exchanger sensor fault. Check sensor and cable. The table classifies it as Lockout (manual reset).…
Lockout
40
Return NTC sensor fault. Check sensor and cable. The table classifies it as Lockout (manual reset).…
Lockout
50
Domestic Hot Water NTC sensor fault. Check sensor and cable. The table classifies it as Lockout (manual reset).…
Lockout
53
Obstruction in flue pipe, Recirculation, Out of Calibration, Poor gas quality. Check for obstruction in flue pipe. Check for recirculation, …
Lockout
55
PCB not programmed. Call authorized SERVICE center. The table classifies it as Lockout (manual reset).…
Lockout
E72/E92
Combustion test alarm during commissioning / calibration. Check flame sensor, check for obstruction in flue pipe, check for recirculation, c…
Lockout
E83
OT Communication Failure. Check OT connection, remove power, reconnect OT connections, if problem persists replace service key. The table cl…
Lockout
84-85
Communication problem between boiler board and control unit. Probable short circuit on wiring. Check cable between control unit and boiler. …
Lockout
86-87
Communication problem between boiler board and control unit. Probable short circuit on wiring. Check cable between control unit and boiler. …
Lockout
109
Pre-circulation alarm (temporary fault). Check correct circulation of water and pump. Check supply and return wiring is correct. The table c…
Lockout
110
Safety thermostat tripped due to over temperature (pump probably blocked or air in heating circuit). Check safety thermostat and cable; chec…
Lockout
117
Hydraulic pressure too high. Relieve pressure via relief valve or drain. Ensure water feed is operating correctly. The table classifies it a…
Lockout
118
Hydraulic pressure too low. Refill heating system by opening cold water tap. The table classifies it as Lockout (manual reset).…
Lockout
125
No circulation of water (control performed via temperature sensor). Check correct circulation of water and pump. Check correct connection of…
Lockout
128
Loss of flame. Check sensing electrode and cable, flue recirculation, electrical continuity between burner and ground, check gas pressure, c…
Lockout
130
NTC flue sensor tripped due to over temperature. Check thermostat, correct circulation of water and pump. Check status of primary exchanger.…
Lockout
131
Thermo fuse tripped due to over temperature or wire harness disconnected from thermo fuse, off the board, or wire harness may be cut. Check …
Lockout
133
Ignition failure. Check correct operation of the condensate trap. Check sensing electrode, spark electrode and cable. Check flue recirculati…
Lockout
134
Gas supply valve blocked. Check gas pressure, sensing electrode, spark electrode and cable, replace PCB if it necessary. Call authorized SER…
Lockout
135
Internal error. Verify all cables. Replace PCB. Call authorized SERVICE center. The table classifies it as Lockout (manual reset).…
Lockout
160
Fan fault. Check fan and cable. The table classifies it as Lockout (manual reset).…
Lockout
162/317
Incorrect power supply frequency. Incorrect power supply frequency. The table classifies it as Lockout (manual reset).…
Lockout
169
Flue pressure switch (contact open). Check pressure switch and cable. Check obstruction on flue pipe. The table classifies it as Lockout (ma…
Lockout
164/384
Fault flame (parasitic flame). Check correct operation of T. gas valve. The table classifies it as Lockout (manual reset).…
Lockout
165/385
Input voltage too low. Check power supply. The table classifies it as Lockout (manual reset).…
Lockout
E178
Low return water temperature / anti-freeze function active. Check the return water sensor, check the circulator, check the correct circulati…
Details
E62
Anti-wind activation with increase of the minimum fan speed. Check the position of the terminal of the flue duct. The table classifies it as…
Details
E63/E65
Combustion level out of range. Check flue recirculation and combustion levels. The table classifies it as Anomaly (fault history display onl…
Details
E65
Maximum value of the speed reached / correction of the flame signal. Check flue recirculation on the flue duct. The table classifies it as A…
Lockout
E67
Antiwind activation at maximum power. Check the position of the terminal of the flue duct. The table classifies it as Anomaly (fault history…
Details
E69
Combustion level out of range. Check flue recirculation and the combustion levels. The table classifies it as Anomaly (fault history display…
Details
E70
Flame signal problem/micro interruption of the flame signal. Check cable and integrity of the sensing electrode, verify the continuity betwe…
Lockout
E73
Combustion adjustment / modified during operation. Review and monitor other codes such as E53 and E92. The table classifies it as Anomaly (f…
Details
Baxi Luna Duo-tec MP heating boilers (fault codes, I&O 7703477.01)
E00
Storage unit PSU parameter not found. Bad connection. Check the wiring. The table classifies it as Lockout (manual reset).…
Lockout
E01
The safety parameters are incorrect. Bad connection. PSU defective. Check the wiring. Replace PSU. The table classifies it as Lockout (manua…
Lockout
E02
Supply temperature sensor short circuited. Sensor fault. Sensor not/poorly connected. Check the wiring. Check that the sensors are operating…
Lockout
E03
Supply temperature sensor open circuit. Sensor fault. Sensor not/poorly connected. Check the wiring. Check that the sensors are operating co…
Lockout
E04
Temperature of heat exchanger too low. Bad connection. Sensor fault. Sensor not/poorly connected. Check the wiring. Replace the sensor if ne…
Lockout
E05
Heat exchanger temperature too high. Bad connection. No circulation. Check that the sensors are operating correctly. Check that the sensors …
Lockout
E06
Return temperature sensor short circuited. Sensor fault. Sensor not /poorly connected. Check the wiring. Check that the sensor has been corr…
Lockout
E07
Return temperature sensor open circuit. Sensor fault. Sensor not/poorly connected. Check the wiring. Check that the sensor has been correctl…
Lockout
E08
Return temperature too low. Bad connection. Sensor fault. Check the wiring. Replace the sensor if necessary. Purge the air in the heating sy…
Lockout
E09
Return temperature too high. Sensor fault. Sensor not/poorly connected. No circulation. Check the wiring. Replace the sensor if necessary. P…
Lockout
E10
Temperature difference between the supply and return temperatures too great. Sensor fault. Sensor not/poorly connected. No circulation. Repl…
Lockout
E11
Temperature difference between the supply and return temperatures too great. Sensor fault. Sensor not/poorly connected. No circulation. Repl…
Lockout
E12
Temperature of heat exchanger is above the normal range (high-limit thermostat STB). Bad connection. Sensor fault. Sensor not/poorly connect…
Lockout
E14
5 burner start-up failures. No ignition: check spark generator wiring, check the ionization/ignition electrode, check the condition of the b…
Lockout
E16
False flame signal. Ionization current present when there should not be a flame. Ignition transformer defective. Gas valve defective. The bu…
Lockout
E17
Problem on the SU PCB. Bad connection. Defective SU PCB. Check the wiring. Inspect the SU PCB and replace it if need be. The table classifie…
Lockout
E34
Fan fault. Fan defective. Bad connection. Replace the fan if need be. Check for adequate draw on the flue connection. The table classifies i…
Lockout
E35
Supply and return reversed. Bad connection. Sensor fault. Sensor not/poorly connected. Water circulation direction reversed. Replace the sen…
Lockout
E36
Flame loss. No ionization current. Purge the gas supply to remove air. Check that the gas valve is fully opened. Check the supply pressure. …
Lockout
E37
Communication error with the SU PCB. Bad connection. Check whether the SU PCB has been correctly fitted in the connector on PCU PCB. The tab…
Lockout
E38
Communication error with the SCU PCB. Bad connection. Defective SCU PCB. Check the wiring. Replace SCU PCB. The table classifies it as Locko…
Lockout
E39
Shutdown input in locked-out mode. Bad connection. External problem. Parameter incorrectly set. Check the wiring. Find external problem. Che…
Lockout
E41
No water temperature change during the deaeration/air purge. Bad connection. Supply/Return sensor damaged. No water circulation. Check the s…
Lockout
E42
Low water cutoff disconnected or water pressure too low. Bad connection. Water pressure low. Check the wiring. Refill the system. Check for …
Lockout
E43
No water temperature change during boiler operation (burner on). Bad connection. Supply/Return sensor damaged. No water circulation. Check t…
Lockout
E44
Difference between supply/return temperature too high. Bad connection. Supply/Return sensor damaged. No water circulation. Check the sensor …
Lockout
Su:0
Parameter error. Parameter error on the PSU PCB. Reset df and dU. Restore parameters. The table classifies it as Shutdown (automatic restart…
Details
Su:1
Maximum supply temperature exceeded. Non-existent or insufficient circulation / sensor error. Check the circulation (direction, pump, valves…
Details
Su:2
Maximum increase of the supply temperature has been exceeded. Non-existent or insufficient water circulation / sensor error. Check the circu…
Details
Su:7
Max difference between T.supply/return exceeded. Non-existent or insufficient circulation / sensor error. Check the circulation (direction, …
Details
Su:8
No release signal. External cause. Parameter error. Bad connection. Correct the external cause. Check the parameters. Check the wiring. The …
Details
Su:9
Line and neutral of power supply are mixed up (if P43=1). Power supply incorrectly wired. Floating or 2 phase network. Line and neutral mixe…
Details
Su:10
Shutdown input is open. External cause. Parameter error. Bad connection. Correct the external cause. Check the parameters. Check the wiring.…
Details
Su:11
Shutdown input active or frost protection active. External cause. Parameter error. Bad connection. Correct the external cause. Check the par…
Details
Su:13
Communication error with the SCU PCB. Bad connection with BUS. SCU PCB not installed in the boiler. Check the wiring. Carry out automatic de…
Details
Su:15
Gas pressure too low. Non-existent or insufficient gas Pressure. Incorrect setting of the Gps gas pressure switch on the SCU PCB. Check that…
Details
Su:16 (1)
Configuration fault or SU PCB not recognized. Wrong SU PCB for this boiler. Replace the SU PCB. The table classifies it as Shutdown (automat…
Details
Su:17 (1)
Configuration fault or default parameter table incorrect. Parameter dF-dU error on the PSU PCB. Reset df and dU. Restore parameters. The tab…
Details
Su:18 (1)
Configuration fault or PSU PCB not recognized. Wrong PSU PCB for this boiler. Replace the PSU PCB. The table classifies it as Shutdown (auto…
Details
Su:19 (1)
Configuration fault or parameters "df-du" unknown. ---. Reset df and dU. Restore parameters. The table classifies it as Shutdown (automatic …
Details
Su:20 (1)
Identification running. ---. No action required. The table classifies it as Shutdown (automatic restart).…
Details
Su:21
Communication error with the SU PCB. Bad connection. Check whether the SU PCB has been correctly fitted in the connector on SU PCB. The tabl…
Details
Su:22
No flame during operation. No ionization current. Purge the gas supply to remove air. Check that the gas valve is fully opened. Check the su…
Lockout
Su:25 (1)
Internal error on the SU-PCb. ---. Replace the SU PCB. The table classifies it as Shutdown (automatic restart).…
Details
Su:29 (2)
tFG sensor above maximum setpoint. Non-existent or insufficient water circulation / sensor error. Replace the flue high limit. Check the cir…
Details
Su:30 (2)
No tFG sensor connected / shorted. Boiler stop. Flue high limit disconnected / Sensor error. Replace the flue high limit. The table classifi…
Details
Su:33
Boiler stop after 5 times tF>tF Max: controlled stop. Non-existent or insufficient circulation / sensor error. Replace the supply sensor. Ch…
Details
Su:34 (2)
Boiler stop after 5 times tFG>tfmax: controlled stop. Non-existent or insufficient circulation / sensor error. Replace the flue high limit. …
Details
Su:35
Insufficient gradient on T1(supply) or T2(return) after burner starts. Non-existent or insufficient circulation / sensor error. Check the ci…
Details
Talk to a boiler technician
Describe what the boiler is doing and get a straight answer about the next step.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.