Baxi Boiler Fault Codes
Baxi Error Codes
Baxi boilers are very reliable with an outstand reputation, but like all things they may breakdown from time to time. luckily Baxi boiler are built with self diagnosing capabilities which show themself in the form of error codes on the LED screen. This helps you as the user to diagnose and if possible repair the boiler getting up and running quickly without the need for costly repairs.
Fortunately for you we have created this guide to help you understand what is wrong with your boiler and give you advice about whether you can repair the boiler yourself or if you need to call a Gas Safe Registered Engineer.
Be advised we do not recommend trying to fix many of the faults yourself this can be very dangerous for you and your family, many faults require specialist equipment and knowledge to calibrate and ensure safe and correct operation. Do NOT remove the boiler case or tamper with any thing inside the boiler.
These error codes are all listed in the boiler installation manual which your installer would have left with you, but its probably quicker and easier to have quick Google search and find the error code on GGB Heating Solutions website.
If your boiler isn’t working and there is no error code check the water (is water coming out of the taps?) electric (is the fuse spur turned on?) and gas (does your gas cooker, hob or fire light?) supplies, one of these may have been switched off by accident. However if you have or had someone carrying work out at your property discuss with them first, incase they have switched them off for some reason.
Feeling unsure and need a professional? GGB Heating Solutions offer boiler diagnostic and repairs from as little as £95 in South Yorkshire Sheffield, Doncaster, Rotherham, Barnsley, Mexborough and surrounding areas.
Baxi Duotec and Platinum boiler Faults
Error Code | Description |
E09 | Gas valve connection fault. |
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 NTC sensor fault – short circuit/open circuit. |
E28 | Flue NTC sensor fault- short circuit/open circuit. |
E40 | Flue NTC sensor fault- short circuit/open circuit. |
E50 | DHW NTC sensor fault (tank boiler) – short circuit/open circuit. |
E83 / E84 / E85 / E86 / E87 | No communication. |
E103 | Safety Assist battery is exhausted. |
E104 | Faulty Safety Assist PCB. |
E107 | PCBs not synchronised. |
E109 | Precirculation alarm. |
E110 | (i) Boiler max. temperature exceeded for gradient (ii) Safety thermostat sensor tripped. |
E118 | Water pressure LOW (<0.5 bar). |
E125 | Water circulation fault. |
E128 | Safety error for frequent loss of flame. |
E129 | Safety error for frequent loss of flame with max correction during ignition during Calibration Function. |
E130 | Flue thermostat sensor tripped (lockout). |
E133 | Gas supply fault. Check the power supply, sensing electrode, spark electrode and cable. |
E134 | Elapsed time gas valve open without gas (short request in a short period). |
E135 | Internal error. |
E154 | Plausibility test (flow/return). |
E160 | Fan fault. |
E270 | Dry fire. |
E317 / 162 | Wrong power supply electrical frequency (Hz). |
E321 / 163 | Domestic Hot Water NTC sensor fault (s.c.). |
E321 / 163 | Domestic Hot Water NTC sensor fault (o.c.). |
E384 / 164 | False flame (parasitic flame). |
E385 / 165 | Under voltage. |
E430 / 166 | Water pressure temporary fault. |
E430 / 166 + Flame ‘crossed’ | Water pressure test failed. |
Blank Screen | Possibly power off. |
Baxi 600, 800 combi and system 2
A Codes
Error Code | Description |
A.00.28 | Solar temperature sensor is either removed or measures a temperature below range. |
A.00.29 | Solar temperature sensor is either shorted or measures a temperature above range. |
A.00.34 | Outdoor temperature sensor expected but not detected. |
A.02.06 | Low system pressure in heating circuit. |
A.02.18 | OBD error. |
A.02.36 | Functional device disconnected. |
A.02.37 | Passive functional device disconnected. |
A.02.45 | Connection error. |
A.02.46 | Device priority error. |
A.02.48 | Unit function configuration error. |
A.02.49 | Failed node initialisation. |
A.02.54 | OpenTherm bus power supply error. |
A.02.55 | Incorrect or missing serial number. |
A.02.76 | Internal memory reserved for full customisation of settings. No further changes can be made. |
E Codes
Error Codes | Description |
E.00.04 | Return temperature sensor disconnected. |
E.00.05 | Return temperature sensor short circuited. |
E.00.16 | DHW tank temperature sensor not connected. |
E.00.17 | DHW tank temperature sensor short-circuited. |
E.00.20 | The flue gas temperature sensor is not connected or measured a temperature below the range. |
E.00.21 | The flue gas temperature sensor has short-circuited or measured a temperature above the range. |
E.01.04 | Flame loss detected five times in 24 hours. |
E.01.12 | Temperature measured by return sensor greater than flow temperature. |
E.01.17 | No water circulation (permanent). |
E.01.20 | Maximum flue gas temperature reached. |
E.02.13 | Total stoppage of the boiler (antifreeze function not active). |
E.02.17 | Permanent communication failure between gas valve and boiler PCB. |
E.02.35 | Critical safety device disconnected. |
E.02.39 | Minimum pressure not reached after 6 minutes of automatic filling. |
E.02.47 | Connection to external device unsuccessful. |
E.04.01 | Flow temperature sensor short circuited. |
E.04.02 | Flow temperature sensor disconnected. |
E.04.03 | Maximum flow temperature exceeded or flow temperature sensor short circuited. |
E.04.08 | Maximum safe temperature value reached. |
E.04.10 | Burner failed to ignite after 4 attempts. |
E.04.12 | Ignition failure -flame monitoring. |
E.04.13 | Fan impeller blocked or maximum rpm exceeded. |
E.04.17 | Fault in gas valve control circuit. |
E.04.18 | The flow temperature is below the minimum temperature or the flow temperature sensor is not connected. |
E.04.23 | Communication internal stoppage. |
E.04.254 | Fault in gas valve control circuit. |
E.04.29 | Communication internal stoppage. |
E.04.54 | Fault in gas valve control circuit. |
H Codes
H.00.42 | Pressure sensor open/faulty. |
H.00.81 | Room unit disconnected. |
H.01.00 | Temporary communication failure between gas valve and boiler PCB. |
H.01.05 | Maximum temperature difference value between flow and return reached. |
H.01.08 | Flow temperature increase in heating mode too quick. Temporary stoppage of 10 minutes. |
H.01.14 | Maximum flow or return temperature value reached. |
H.01.18 | No water circulation (temporary). |
H.01.21 | Flow temperature increase during domestic hot water operation too fast. |
H.02.00 | Reset in progress. |
H.02.02 | Waiting for configuration settings to be entered (CN1,CN2). |
H.02.03 | Configuration settings (CN1,CN2) not entered correctly. |
H.02.04 | PCB settings cannot be read. |
H.02.05 | Setting memory not compatible with the boiler PCB type. |
H.02.07 | Low pressure in heating circuit (permanently). |
H.02.09 | Partial stoppage of the boiler (antifreeze function active). |
H.02.10 | Total stoppage of the boiler (antifreeze function not active). |
H.02.70 | External unit heat recovery test failed. |
H.03.00 | No identification data for boiler safety device. |
H.03.02 | Temporary flame loss. |
H.03.05 | Power supply voltage too low. |
H.03.54 | Temporary flame loss. Shutdown due to the power supply voltage being too low. |