Low
Running lamp flashing on Malvern TenTwenty

Your boiler is currently in a normal waiting period and will start back up automatically in a few minutes.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

The boiler has a built-in delay timer.

From this model's manual
Verified against the Malvern Tentwenty installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for approximately 3 to 5 minutes for the anti-cycle timer to finish.Ensure the room thermostat is turned up to call for heat.Check that the clock or programmer is set to 'On'.

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