Low Warning
Summer mode LED on Glow-worm Compact

Your boiler is failing to switch into summer mode due to an internal electronic circuit board failure.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Failure to illuminate when button pressed - Change P.C.B.

What causes this fault?

This fault occurs when the internal electronic components responsible for registering button presses on the control panel have degraded or failed. The most common reason is a physical breakdown of the circuitry on the printed circuit board, which prevents the boiler from acknowledging the command to switch modes.

This issue is often discovered in late spring or early summer when homeowners attempt to switch off their central heating for the warmer months.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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