Medium Information
YELLOW LED Solid on Vokera Compact 29

Your boiler has entered a test mode and is currently unable to provide normal heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Check JP1

What causes this fault?

This fault occurs when the boiler has been accidentally switched into 'Combustion Analysis' or 'Service' mode. The most common reason is that the control selector knob was turned too far or left in a specific position meant only for engineers to test the gas levels. While in this state, the boiler ignores your thermostat and hot water taps to run at a fixed output for testing purposes.

DIY fix possible

Locate the selector dial on the front control panel.Turn the dial to the 'OFF/RESET' position.Wait five seconds, then turn the dial back to your desired 'Heating and Hot Water' setting.

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