Error Codes Boilers
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Baxi Combi Boilers
Baxi combi boilers supply quick access to hot water directly from the mains water supply using a space-saving wall mounted unit that is normally located in a bathroom or kitchen and hidden within a cupboard. Baxi combi boilers reduce energy bills due to being A rated high efficiency boiler and are ideally suited to apartments and small to medium sized houses with low to moderate usage. Baxi combi boilers don’t require hot water tanks or cylinders as a regular boiler or system boiler does therefore making these Baxi combi boilers more cost-effective to install.
Baxi System Boilers
Baxi Regular Boilers
| Fault Code | Possible Cause |
|---|---|
| E20 | Central heating NTC error |
| E28 | Error with the NTC (Negative Temperature Coefficient) flue, air pressure switch or blocked flue or condensate |
| E50 | Hot water NTC (Negative Temperature Coefficient) error |
| E110 | Thermostat operated safety |
| E119 | Water pressure switch error – not operated. |
| E125 | Primary circuit error circulation fault |
| E130 | Flue NTC (Negative Temperature Coefficient) operation error |
| E133 | Gas supply error or flame failure |
| E160 | Fan or fan wiring error |
| E193 | Pre-circulation error |
| Fault Code | Possible Cause |
|---|---|
| 110 | Overheated – try bleeding your radiators |
| 117 | Water pressure too high |
| 118 | Water pressure too low |
| 125 | Water circulation fault |
| 133 | Safety time to establish flame exceeded |
| E10 | Outdoor sensor error |
| E20 | Central heating thermistor sensor fault |
| E28 | Flue thermistor fault |
| E54 | Domestic hot water (DHW) flow sensor fault |
| E78 | Water pressure sensor fault |
| E100 | Internal clock time error on printed circuit board (PCB) |
| E109 | Poor circulation |
| 110 | Overheat – try bleeding your radiators |
| 111 | Maximum limit of flow temperature |
| 117 | Water pressure too high |
| 118 | Water pressure too low |
| 119 | System pressure too low |
| 125 | Water circulation fault |
| 127 | Legionella (cause of Legionnaires’ disease) protection temperature not reached |
| 128 | Loss of flame during operation |
| 133 | Safety time to establish flame exceeded |
| 153 | Forced reset unit unlocked |
| 160 | Fan fault |
| 162 | Air pressure switch error |
| 164 | Pressure Sensor Error (UK) – Heating flow switch error (Ireland) |
| 166 | Air pressure switch fault |
| 270 | Dry fire |
| 432 | Earth connector error |
| 433 | Heat exchanger temperature exceeded (greater than 95 degrees) |
| Fault Code | Possible Cause |
|---|---|
| 1 green flash | Boiler temperature reached. No action required. |
| 3 green flashes | Temporary flame loss. Boiler will self reset, if fault continues you will see 3 red flashes. |
| 4 green flashes | Communication error between printed circuit board (PCB) and control. Temporary error, will self reset. |
| 5 green flashes | Parameter error on printed circuit board (PCB). Temporary error, will self reset |
| 6 green flashes | Miscellaneous error. Temporary error, will self reset. |
| 1 red flash | Sensor error, temperature fault or flow fault. |
| 2 red flashes | Boiler overheat tripped |
| 3 red flashes | Ignition fault. Boiler has attempted to light 5 times and failed. |
| 4 red flashes | Fan fault |
| 5 red flashes | Parameter storage unit (PSU) error. |
| 6 red flashes | Miscellaneous error. |
| Fault Code | Possible Cause |
|---|---|
| E10 | Outdoor sensor fault |
| E20 | Central heating thermistor sensor error |
| E28 | Flue thermistor error |
| E110 | Boiler overheat error |
| E119 | Low water pressure error |
| E125 | Primary water circulation error |
| E131 | Flue overheat lockout error |
| E133 | Ignition error |
| E160 / E161 | Fan error |
| E164 | Pressure sensor fault |
| E167 | Printed circuit board (PCB) error |
| E168 | Printed circuit board (PCB) lockout error |
| E193 | Circulation error |
| Fault Code | Possible Cause |
|---|---|
| H.01 – .00 | Loss of communication between gas valve and boiler board. Possible fault in air/gas unit or loose connection to gas valve. |
| H.01 – .05 | Difference between the flow and return temperature is too high, sensor error or insufficient circulation. |
| H.01 – .08 | Sensor fault, flow temperature increasing too fast in heating mode or insufficient circulation. |
| H.01 – .14 | Maximum flow temperature value exceeded or insufficient circulation – temporary fault. |
| H.01 – .18 | No water circulation, insufficient circulation or sensor error. |
| H.01 – .21 | Temporary error – flow temperature increasing too fast in domestic hot water (DHW) mode, insufficient circulation or sensor error. |
| H.02 – .02 | Temporary error – no input of parameters C1/C2. Printed circuit board (PCB) not configured. |
| H.02 – .03 | Temporary error- incorrect configuration settings C1/C2. |
| H.02 – .04 | Temporary error- parameter fault. Incorrect parameters. |
| H.02 – .06 | Temporary error caused by system water pressure, water leak on boiler, water leak on system. |
| H.03 -.00 | Temporary error with communication, negative temperature coefficient thermostat (NTC) or flue sensor. Sensor could also be unconnected or have a bad connection. |
| H.03 – .01 | Communication error with the printed circuit board (PCB) |
| H.03 – .02 | Flame error – no flame during operation. |
| E.00 – .04 | Return temperature sensor open-circuit. Sensor not or badly connected. |
| E.00 – .05 | Return temperature sensor short-circuit. Sensor not connected or badly connected. |
| E.01 – .02 | Temperature measured by return sensor greater than flow sensor. |
| E.01 – .04 | Loss of flame detected 5 times in 24 hours (with burner on). |
| E.01 – .11 | Incorrect fan speed – external draught over the boiler or defective gas/air unit. |
| E.01 – .12 | Requires reset – temperature measured by return sensor greater than flow temperature. |
| E.01 – .17 | Reset the boiler – no circulation, sensor fault either not connected or has a bad connection. |
| E.01 – .20 | Maximum flue gas temperature reached. No circulation or sensor fault. |
| E.02 – .00 | Reset button has been pressed. |
| E.02 – .07 | No or low system water pressure. system pressure less than 0.5bar |
| E.02 – .16 | Permanent fault caused by channel service unit (CSU) time-out or printed circuit board (PCB) damage. |
| E.02 – .17 | Loss of communication between gas valve and boiler printed circuit board (PCB) or fault in air/gas unit. |
| E.02 – .19 | Jumper 1 changed – check position of jumper 1. |
| E.02 – .20 | Jumper 2 changed – check position of jumper 2. |
| E.02 – .21 | Jumper 3 changed – check position of jumper 3. |
| E.02 – .47 | Wiring to external device error. |
| E.02 – .48 | Configuration to external device unsuccessful – check pairing to external device. |
| E.04 – .00 | Gas valve error – gas valve not detected. |
| E.04 – .01 | Flow temperature sensor short-circuited. Sensor not or badly connected, bad connection or sensor fault. |
| E.04 – .02 | Permanent fault. Flow temperature sensor open-circuited, sensor not or badly connected, bad connection or sensor fault. |
| E.04 – .03 | Permanent fault. Critical flow temperature reached, non-existent or insufficient circulation. |
| E.04 – .04 | Permanent fault. Flue temperature sensor short-circuited, sensor not or badly connected, bad connection or sensor fault. |
| E.04 – .05 | Permanent fault. Flue temperature sensor short-circuited, sensor not or badly connected, bad connection or sensor fault. |
| E.04 – .06 | Permanent fault. Critical flue gas temperature value reached, no circulation or sensor fault. |
| E.04 – .08 | Permanent fault. Maximum safe temperature value reached, safety thermostat open-circuited, no circulation, sensor not or badly connected, bad connection or sensor fault. |
| E.04 – .10 | Failure to light (could be gas supply issue). |
| E.04 – .12 | Permanent fault. False flame signal, short-term fluctuation of the mains, ionization current present even though there is no flame, the burner remains very hot (CO2 too high) or defective gas/air unit. |
| E.04 – .13 | Permanent fault. Fan rotor blocked, fan seized or wiring to fan damaged. |
| E.04 – .17 | Permanent fault. Problem with gas valve or defective gas/air unit. |
| Fault Code | Possible Cause |
|---|---|
| E09 | Gas valve connection cable. |
| E10 | External probe fault. |
| E12 | Differential water flow switch fault (still open). |
| E13 | Differential water flow switch fault (still closed). |
| E15 | Gas valve command fault. |
| E20 | Central heating negative temperature coefficient (NTC) thermostat fault. |
| E28 | Flue negative temperature coefficient (NTC) thermostat fault. |
| E40 | Central heating return negative temperature coefficient (NTC) thermostat fault. |
| E50 | Domestic hot water (DHW) negative temperature coefficient (NTC) thermostat sensor fault (tank boiler) (s.c.) or DHW NTC sensor fault (tank boiler) (o.c.). |
| E83/E84/E85/E86/E87 | No communication. |
| E109 | Pre-circulation fault. |
| E110 |
|
| E118 | Primary system water pressure too low (< 0.5 bar). |
| E125 | Circulation fault (primary). |
| E128 | Frequent flame failure (12 times). |
| E129 | Safety error for frequently loss of flame with max correction during the ignition during Calibration Function. |
| E130 | Flue thermostat sensor tripped (lockout). |
| E133 | Failure to light (could be a gas supply issue). |
| E134 | Elapsed time gas valve open without gas (short request in a short period) |
| E135 | Interruption of gas supply (internal error). |
| E154 | Flow/return sensor temperature test. |
| E160 | Fan or fan wiring fault. |
| E163 | Domestic hot water (DHW) negative temperature coefficient (NTC) thermostat sensor fault (s.c.) or DHW NTC sensor fault (o.c.). |
| E270 | Circulation fault (dry fire). |
| E317 | Wrong power supply electrical frequency (Hz). |
| E321 | Hot water negative temperature coefficient (NTC) fault. |
| E384 | False flame. |
| E385 | Under voltage. |
| E430 | Water pressure temporary test. |
| E430 + Flame ‘crossed’ | Water pressure test failed. |
| Fault Code | Possible Cause |
|---|---|
| 1 Green Flash | Boiler temperature reached – no action required |
| 3 Green Flashes | Temporary flame loss – this is a temporary error, the system should reset on its own |
| 4 Green Flashes | Communication error between printed circuit board (PCB) and Control – this is a temporary error, the system should reset on its own |
| 5 Green Flashes | Parameter error on parameter storage unit (PSU) or printed circuit board (PCB) – this is a temporary error, the system should reset on its own. |
| 6 Green Flashes | Miscellaneous error |
| 1 Red Flash | Sensor error, sensor fault, temperature fault or flow fault – this is a temporary error, the system should reset on it’s own. |
| 2 Red Flashes | Boiler overheat tripped |
| 3 Red Flashes | Ignition fault. Boiler has attempted to light 5 times and failed |
| 4 Red Flashes | Fan Fault |
| 5 Red Flashes | Parameter storage unit (PSU) error |
| 6 Red Flashes | Miscellaneous |
| Fault Code | Possible Cause |
|---|---|
| E0 | Temperature sensor fault |
| E1 | Overheated – try bleeding your radiators |
| E2 | Poor circulation – try bleeding your radiators |
| E3 | Printed circuit board (PCB) fault |
| E4 | Ignition failure – try bleeding your radiators |
| E10 | Poor/No circulation |
| E12 | Printed circuit board (PCB) Fault |
| E13 | Heat exchanger thermal fuse tripped |
| E83 / 84 / 85 / 86 / 87 | Fan fault normally E8 |
| Fault Code | Possible Cause |
|---|---|
| E53 | Poor combustion – flue terminal may be blocked |
| E110 | Overheated – try bleeding your radiators |
| E117 | System water pressure high – try bleeding water from your radiators |
| E118 | System water pressure low |
| E125 | Overheat – try bleeding your radiators |
| E133 | Gas supply fault |
| E4 | Ignition failure |
| E09 | Gas valve wiring fault |
| E10 | Outdoor sensor error |
| E15 | Gas valve connection fault |
| E20 | Central heating thermistor sensor fault |
| E28 | Flue thermistor fault |
| E40 | Central heating return thermistor fault |
| E53 | Flue obstruction |
| E55 | Calibration required |
| E78 | Water pressure sensor fault |
| E92 | Combustion test alarm during auto-setting |
| E109 | Poor circulation |
| E110 | Boiler overheat tripped |
| E117 | System pressure high (>2.9 Bar) |
| E118 | System pressure low(< 0.5bar) |
| E125 | Primary water circulation fault |
| E128 | Loss of flame during operation |
| E129 | Loss of flame during calibration |
| E133 | Ignition fault |
| E135 | Internal error |
| E154 | Primary flow fault |
| E160 | Fan fault |
| E270 | Dry fire |
| E317 | Wrong power supply (Hz) |
| E321 | Not water thermistor fault |
| E384 | Flame detected when gas valve off |
| E385 | Low voltage (less than 195v) |
| Fault Code | Possible Cause |
|---|---|
| FLASH FLASH ON | Fan error |
| FLASH OFF FLASH | Voltage less than 180V |
| FLASH OFF ON | Overheat lockout |
| FLASH ON FLASH | Printed circuit board (PCB) error |
| FLASH ON ON | Printed circuit board (PCB) fault |
| OFF OFF OFF | No power |
| ON FLASH FLASH | Circulation error or dry fire |
| ON FLASH ON | Thermistor error |
| ON OFF FLASH | Live and neutral reversed error |
| ON OFF ON | Ignition lockout error |
| ON ON FLASH | Printed circuit board (PCB) error |
| ON ON ON | Low voltage wiring harness error |