Potterton Performa System HE Fault codes & diagnostics

7 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

System Natural GasLPG 12-28 kW 2002-2011 Discontinued

Replaced by: Promax System HE

Choose your boiler type

The Performa range comes in 8 types

Pick the one you have. The fault codes, GC numbers and manual differ by type.

12e 7 codes · 1 GC number 18e 7 codes · 1 GC number 24e 7 codes · 1 GC number 28e 7 codes · 1 GC number 12 HE 7 codes · 1 GC number 18 HE 7 codes · 1 GC number 24 HE 7 codes · 1 GC number 28 HE 7 codes · 1 GC number
Each model has its own manual A family spans several manuals, one per model or generation. Pick your model above and its page has the manual its fault codes were read from.

This boiler uses LED flash patterns

Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →

Severity at a glance

Each cell = one fault code. Hover to identify.
1 Emergency 6 High
Just want the most common Potterton Performa System HE faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 7 documented codes

Tap any card for details

LED / flash-pattern codes
neon flashing

Your boiler has detected an internal electrical or mechanical fault that is preventing it from circulating water around your home.

High Engineer only £180-350 Shared across the Performa System range

Parts commonly replaced

  • Circulation Pump
  • Main Control Board (PCB)
Full explanation for neon flashing
Digital codes
20

Your boiler has stopped working because it failed to light properly or the waste water pipe is blocked.

High DIY-safe £100-£280 Shared across the Performa System range

What to check first

  1. Check that your gas pre-pay meter hasn't run out of credit.
  2. Inspect the white plastic pipe (condensate pipe) outside to see if it is frozen or blocked.
  3. Attempt to reset the boiler by turning the control knob to 'R' for five seconds.

Parts commonly replaced

  • Flame sensing electrode
  • Gas valve
  • Ignition lead
Full explanation for 20
21

Your boiler has shut down because its internal safety sensors detected that it was beginning to overheat.

High DIY-safe £100-280 Shared across the Performa System range

What to check first

  1. Ensure all radiator valves are fully open to allow water to circulate
  2. Check that the boiler pressure is between 1.0 and 1.5 bar on the gauge
  3. Allow the boiler to cool down, then turn the selector switch to 'R' for five seconds to reset

Parts commonly replaced

  • Overheat Thermostat
  • Pump
  • Main Heat Exchanger
  • NTC Sensor
Full explanation for 21
23

Your boiler has stopped working because either there isn't enough water pressure in the system or the internal pump is unable to circulate water.

High DIY-safe £180-350 Shared across the Performa System range

What to check first

  1. Check the pressure gauge on the front of the boiler; if it is below 1 bar, it needs topping up.
  2. Locate the filling loop (usually a silver flexible hose) underneath the boiler.
  3. Slowly open the valves until the pressure reaches 1.5 bar, then close them tightly.
  4. Reset the boiler to see if the fault clears.

Parts commonly replaced

  • Circulating Pump
  • Pressure Sensor
  • Expansion Vessel Re-charge
Full explanation for 23
24

Your boiler has detected a problem with its internal temperature sensors, meaning it cannot accurately measure how hot the water is and has shut down as a safety precaution.

High Engineer only £90-160 Shared across the Performa System range

Parts commonly replaced

  • Central Heating (CH) Temperature Sensor
  • NTC Thermistor
  • Wiring Harness

Related codes

Full explanation for 24
25

Your boiler has detected that a temperature sensor is not working correctly, which has caused the system to stop running to prevent overheating.

High Engineer only £90-160 Shared across the Performa System range

Parts commonly replaced

  • NTC Temperature Sensor
  • Wiring harness
Full explanation for 25
Pressure of 3 or greater

Your boiler's internal water pressure has climbed too high, which means the system is under too much strain and needs to be brought back down to normal levels.

Emergency DIY-safe £80-150 Shared across the Performa System range

What to check first

  1. Check that the silver filling loop valves are tightly closed
  2. Bleed water from a radiator using a bleed key to reduce pressure
  3. Monitor the pressure gauge to ensure it returns to between 1 and 1.5 bar
  4. If pressure continues to rise, turn off the mains water stop tap and call an engineer

Parts commonly replaced

  • Pressure relief valve
  • Filling loop
  • Expansion vessel
Full explanation for Pressure of 3 or greater
Status & diagnostic codes

4 operating states & engineer diagnostics

Not faults — these are normal operating states. Tap to expand.

10 Status Your boiler is simply indicating that it has successfully completed its startup process and is currently powered on. 11 Status Your boiler is operating normally and performing a standard self-check or heating cycle. 12 Status Your boiler is operating exactly as it should and is currently burning gas to heat your home or water. neon illuminated Status Your boiler is currently on and operating normally as part of its internal power check.