BoilerFaultCodesYour boiler has switched itself off because the water pressure in the system has dropped too low to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: low water pressure error
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.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath your boiler.Slowly open the small tap(s) on the loop until you hear water entering the system.Watch the pressure gauge and close the taps once the needle reaches between 1.0 and 1.5 bar.Check that the error code has cleared; you may need to press 'Reset'.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E119 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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