Error codes

Your Potterton boiler may display an error code if it's experiencing technical problems. Depending on your boiler model, the error code may be displayed as either a letter and number or a series of flashing lights.

Different codes refer to different errors. Some of these can be fixed by simply resetting your boiler, while others will require an engineer. If your boiler is displaying an error code which isn't listed below, please contact Baxi Customer Support on 0344 871 1560*

If you're a tenant in social housing, please contact your housing association or landlord who will be able to assist you with any issues to do with your boiler.

For product information, please visit our Literature Library.

* Calls to 03 numbers will cost the same as calls to standard landline numbers, and will be included as part of any inclusive call minutes or discount schemes for geographic calls.

  • Promax Combi, System & Store
  • Potterton Promax Ultra
  • Gold Combi and System & Titanium Combi

Error Code

Possible fault

 E10  Outdoor sensor error
 E20  Central heating thermistor sensor fault
 E28  Flue thermistor fault
 E50  Domestic hot water sensor fault
 E110  Boiler overheat tripped
 E119  System pressure low (<0.5 bar)
 E125  Primary water circulation fault
 E130  Flue thermostat sensor tripped (lockout)
 E131  Flue overheat lockout
 E133  Ignition fault
 E151  PCB error
 E152  PCB error
 E160  Fan fault
 E161  Fan fault
 E164  Domestic hot water sensor error (In the ROI this is a heating flow switch error)
 E167  PCB fault

 E168

 PCB lock out
E193  Circulation

 Error code 

 Possible fault 

 E09   Gas valve wiring fault
 E10  Outdoor sensor error

 E15

 Gas valave connection fault
 E20  Central heating thermistor sensor fault
 E28  Flue thermistor fault
 E40  Central heating return thermistor fault
 E50  Domestic hot water sensor fault
 E53  Flue obstruction
 E55  Calibration required
 E78  Water pressure sensor fault
 E83/84/85/86/87  No communication between room controller and boiler
 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 (<0.5 bar)
 E125  Primary water circulation fault
 E128  Loss of flame during operation
 E129  Loss of flame during calibration
 E130  Flue thermostat sensor tripped (lockout)
 E133  Ignition fault
 E135  Internal error
 E154  Primary flow fault
 E160  Fan fault
 E270  Dry fire
 E317  Wrong power supply (HZ)
 E321  Hot water thermistor fault
 E384  Flame detected when gas valve off (false flame)
 E385  Low voltage (less than 195v)

Error code

Possible fault

E09 Gas valve wiring fault
E10 Outdoor sensor error

E15

Gas valave connection fault
E20 Central heating thermistor sensor fault
E28 Flue thermistor fault
E40 Central heating return thermistor fault
E50 Domestic hot water sensor fault
E53 Flue obstruction
E55 Calibration required
E78 Water pressure sensor fault
E83/84/85/86/87 No communication between room controller and boiler
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 (<0.5 bar)
E125 Primary water circulation fault
E128 Loss of flame during operation
E129 Loss of flame during calibration
E130 Flue thermostat sensor tripped (lockout)
E133 Ignition fault
E135 Internal error
E154 Primary flow fault
E160 Fan fault
E270 Dry fire
E317 Wrong power supply (HZ)
E321 Hot water thermistor fault
E384 Flame detected when gas valve off (false flame)
E385 Low voltage (less than 195v)

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