Vokera Maxin Fault codes & diagnostics

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

Combi Natural Gas 24-28 kW 2000-2005 Discontinued

Replaced by: Linea

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Severity at a glance

Each cell = one fault code. Hover to identify.
7 High 2 Low
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The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 9 documented codes

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Check JP1

Your boiler has detected an internal setting error—usually a missing jumper pin—on its main control board which is preventing it from starting.

High Engineer only £120-350

Parts commonly replaced

  • Main Printed Circuit Board
  • Jumper Pin JP1
Full explanation for Check JP1
GREEN LED On every 0.5-secs

Your boiler is struggling to start up correctly or is detecting low water pressure and is currently in a temporary pause mode.

High DIY-safe £80-250

What to check first

  1. Check the pressure gauge on the front of the boiler; if it is below 1 bar, top it up to 1.5 bar using the filling loop.
  2. Restart the boiler by turning the mode selector switch to 'OFF/RESET' and then back to 'ON'.
  3. Ensure there are no obstructions in the external flue pipe (the white pipe leading outside).

Parts commonly replaced

  • Air Pressure Switch
  • Fan
  • Water Pressure Sensor

Related codes

Full explanation for GREEN LED On every 0.5-secs
GREEN LED On every 6-secs

Your boiler is in standby mode and is operating exactly as it should while waiting for a request for heating or hot water.

Low DIY-safe

What to check first

  1. No action is required as this indicates normal operation.
  2. If you have no heating, check that your thermostat is turned up.
  3. Ensure your programmer or timer is set to an 'On' period.
Full explanation for GREEN LED On every 6-secs
GREEN LED Solid

Your boiler is working normally and is currently heating your home or providing hot water as requested.

Low DIY-safe

What to check first

  1. Check your thermostat or programmer settings if you did not expect the heating to be on
  2. Ensure all hot water taps are fully closed
  3. Simply wait for the boiler to finish its current heating cycle

Related codes

Full explanation for GREEN LED Solid
Pressure < 0.5 bar

Your boiler has stopped working because the water pressure is too low for the system to run safely.

High DIY-safe £0-120

What to check first

  1. Locate the filling loop (usually a silver braided hose underneath the boiler).
  2. Slowly open the valve or valves until you hear water flowing into the system.
  3. Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the valves tightly.

Parts commonly replaced

  • Filling loop valve
  • Expansion vessel
  • Pressure relief valve
Full explanation for Pressure < 0.5 bar
RED LED On every 0.5-secs

Your boiler has entered a permanent lockout mode because it failed to start safely or detected a critical hardware failure.

High DIY-safe £100-350

What to check first

  1. Check that your gas pre-pay meter has credit (if applicable).
  2. Ensure your boiler pressure gauge is between 1 and 1.5 bar; top up if it is too low.
  3. Turn the mode selector dial to 'OFF/RESET' for 10 seconds, then back to the desired setting.

Parts commonly replaced

  • Primary NTC Thermistor
  • Ignition Electrode
  • PCB
  • Gas Valve
Full explanation for RED LED On every 0.5-secs
RED LED Solid

Your boiler has switched itself off because it has detected that the water inside has become too hot.

High DIY-safe £100-250

What to check first

  1. Check that all radiator valves are open to allow water to flow.
  2. Ensure the boiler pressure gauge is between 1 and 1.5 bar; top up if it is too low.
  3. Turn the mode selector switch to 'OFF/RESET' for a few seconds, then back to the heating/hot water icon.

Parts commonly replaced

  • Limit Thermostat
  • Circulation Pump
  • Heat Exchanger
Full explanation for RED LED Solid
Reset light illuminated

Your boiler has stopped working because it failed to light the flame or has reached an unsafe temperature.

High DIY-safe £100-350

What to check first

  1. Check that your gas meter has credit and the isolation valve is open.
  2. Turn the control knob to the 'Reset' position for a few seconds and then back to 'On'.
  3. Ensure your radiator valves are open and the system pressure is between 1 and 1.5 bar.

Parts commonly replaced

  • Ignition Electrode
  • Gas Valve
  • Overheat Thermostat
Full explanation for Reset light illuminated
YELLOW LED Solid

Your boiler is stuck in a service mode typically used by engineers, meaning it may not respond to your normal heating or hot water controls.

High Engineer only £90-180

Parts commonly replaced

  • Main PCB
  • Jumper Pin JP1

Related codes

Full explanation for YELLOW LED Solid