Low
Green light flashing slowly on Potterton Prima 30B

Your boiler is currently in standby mode and is working correctly, simply waiting for your thermostat or programmer to tell it that you need heat.

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

Standby or lack of call for heat (Switch live demand)

From this model's manual
Verified against the Potterton Prima 30b 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

Check your room thermostat is turned up to a temperature higher than the current room temperature.Ensure your heating timer or programmer is set to 'ON' for the current time period.Verify that the hot water cylinder thermostat is also calling for heat if you have a system with a hot water tank.

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