Low
Thermostat + on Potterton Ultra 2 30 DV

Your boiler is correctly receiving a signal from your thermostat that it needs to turn on, so this light simply indicates that your heating or hot water is currently in active mode.

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

Indicator light on control panel signaling heat demand/thermostat status

From this model's manual
Verified against the Potterton Ultra 2 30 Dv 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.

Engineer required

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

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