Vokera Easi-Heat Plus 25C Fault codes & diagnostics

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

Combi Natural Gas 2016-present
GC Number 47-364-29
Download the Vokera Easi-Heat Plus 25C manualThe official installation and service manual (PDF). PDF

The fault code is already on your display

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

Fault codes

All 4 documented codes

Tap any card for details

Alarm high limit thermostat

Your boiler has detected that it is dangerously overheating and has automatically shut itself down to prevent damage.

High Engineer only £150-300 Shared across the Easi-Heat Plus range

Parts commonly replaced

  • High limit thermostat
  • Pump
  • Diverter valve
  • PCB
Full explanation for Alarm high limit thermostat
Alarm system water pressure

Your boiler has detected that the water pressure inside your heating system is too low to operate correctly.

High DIY-safe £80-150 Shared across the Easi-Heat Plus range

What to check first

  1. Locate the filling loop (a flexible silver hose) underneath the boiler
  2. Slowly turn the small valve(s) to allow mains water into the system
  3. Monitor the pressure gauge until the needle is between 1.0 and 1.5 bar
  4. Close the valve(s) tightly to stop the flow

Parts commonly replaced

  • Filling loop
  • Pressure relief valve
  • Pressure sensor
Full explanation for Alarm system water pressure
Fault sensors

Your boiler's temperature sensors are giving conflicting or invalid readings, so it has stopped working to prevent potential damage.

High Engineer only £120-200 Shared across the Easi-Heat Plus range

Parts commonly replaced

  • NTC sensor
  • Wiring harness
Full explanation for Fault sensors
Temporary fault

Your boiler has detected a brief hiccup in its internal systems and is pausing operation to protect itself.

Low DIY-safe Shared across the Easi-Heat Plus range

What to check first

  1. Locate the reset button or dial on the front of the boiler display panel
  2. Press and hold the reset button for 3 to 5 seconds
  3. Wait a few minutes to see if the boiler resumes normal operation
Full explanation for Temporary fault
Status & diagnostic codes

4 operating states & engineer diagnostics

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

Boiler stand-by Status Your boiler is currently in standby mode and is working exactly as it should, waiting for a signal from your thermostat or hot water tap to start heating. Flame ON Status Your boiler's electronic control system is incorrectly detecting a flame inside the unit even when it should be turned off, which is a safety concern that prevents it from starting up correctly. Purge cycle mode active Status Your boiler is currently performing an automatic air-removal process to clear trapped air from the system and is not actually broken. Service operation Diagnostic Your boiler has reached its programmed time for a routine annual safety inspection and professional service.
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