Low
ON every 0.5-secs (Green LED) on Vokera Sabre 29HE

Your boiler is pausing temporarily due to a minor safety check, such as a drop in system water pressure or a momentary blocked air signal.

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

Temporary fault, e.g.: APS fault, low water pressure

From this model's manual
Verified against the Vokera/Vokera Sabre 29he 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 the pressure gauge on the front of your boiler to ensure it is sitting between 1 and 1.5 bar.If the pressure is below 1 bar, use the filling loop underneath the boiler to top it back up.Turn the boiler off and on again at the mains switch to reset the temporary fault.

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Related fault codes

Red LED flashingView →Lockout faultView →

All 9 fault codes on the Sabre 29HE

Seeing a different code? Every code this model can display, in one place.

DHW NTC faultFlashing 8-times a secondON every 0.5-secs (Red LED)ON every 0.5-secs (Yellow LED)ON every 6-secsSolid (Green LED)Solid (Red LED)Solid (Yellow LED)

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