High Lockout
E119 on Baxi Duo-tec/Megaflo

Your boiler has switched itself off because the water pressure in the system has dropped too low to operate safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Water Pressure Switch Not Operated

What causes this fault?

This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to fire up. The most common reasons are a slow leak from a radiator valve or pipework, or the pressure being manually bled out of the system during radiator venting.

This fault is frequently seen in autumn when homeowners turn their heating back on for the first time after summer, revealing pressure drops that occurred while the system was idle.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E125View →

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