Low
03 on Grant Spira

Your boiler is currently idle and waiting for a signal from your thermostat or internal settings to tell it that your home needs more 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

BOILER WAIT THERMOSTAT: Boiler is in standby awaiting a switched live input signal or boiler temperature to drop below set point.

From this model's manual
Verified against the Grant Spira installation & service manual, page 57.
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 temperatureEnsure your heating programmer or central heating timer is set to 'On'Check that any external weather compensation sensors are not faulty or obscured

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