BoilerFaultCodes.com

Potterton Promax Fault Codes

CombiSystemRegular Natural GasLPG 12-33 kW 2006-2018 Discontinued
GC Numbers: 47-393-0647-393-0747-393-0841-591-9141-591-9241-591-9341-591-9441-591-9541-592-2341-592-2441-592-5641-592-2541-592-2641-592-2741-592-2841-592-2947-393-2747-393-2847-393-2947-393-3047-393-31

Replaced by: Baxi 800

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Most common fault codes

E20
Your boiler is struggling to monitor its temperature correctly because a internal sensor is sending a faulty signal, preventing the heating from working properly.
Gas Safe engineer required · £90-160
E28
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Gas Safe engineer required · £100-£180
E110
Your boiler has switched itself off because it has become too hot internally and needs to cool down for safety.
May be DIY safe · £100-£350

All 18 fault codes

Code Severity Plain English
E10 Low Your boiler has lost communication with the sensor that monitors the weather outside, meaning it may not heat your home as efficiently as usual.
E20 High Your boiler is struggling to monitor its temperature correctly because a internal sensor is sending a faulty signal, preventing the heating from working properly.
E28 High Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
E50 Medium Your boiler has detected a problem with the sensor that monitors the temperature for your taps, meaning you may have inconsistent or no hot water.
E110 High Your boiler has switched itself off because it has become too hot internally and needs to cool down for safety.
E119 High Your boiler has stopped working because the water pressure in the system has dropped too low and needs topping up.
E125 High Your boiler has detected that water is not moving through the system correctly, which could be due to a blockage or a pump failure.
E130 High Your boiler has shut itself down because the exhaust gases have reached a temperature that is too high, which is a safety feature to prevent damage.
E131 High Your boiler has shut down because the exhaust gases have reached a dangerously high temperature, triggering a safety sensor to prevent damage.
E133 High Your boiler has failed to light, which is usually caused by a temporary interruption in the gas supply or a frozen condensate pipe.
E151 High Your boiler's computer control board has developed a fault and can no longer communicate with the system components, causing the unit to shut down for safety.
E152 High Your boiler’s internal computer has developed a fault and is struggling to process information correctly.
E160 High Your boiler has stopped working because the fan that clears away waste gases is not spinning correctly or has lost communication with the control board.
E161 High Your boiler has stopped working because the fan used to clear out waste gases is not spinning at the correct speed or has failed to start.
E164 High Your boiler has detected a problem with the sensor that monitors your hot water temperature or a switch that controls water flow, which usually means your hot water will stop working properly.
E167 High Your boiler's internal computer has developed a fault and can no longer control the heating or hot water safely.
E168 High Your boiler has detected an internal electrical error that is preventing it from running safely, and it usually means the main control board is confused or failing.
E193 High Your boiler is struggling to move water around the system properly, which is causing it to shut down to prevent overheating.

Potterton Promax is discontinued — time for a new one?

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

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