BoilerFaultCodesYour boiler has stopped working because the water pressure in the system has dropped too low and needs topping up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System pressure too low
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to operate safely. The most common reasons are a slow leak from a radiator valve or pipework, or the air being released from the system through recent bleeding of the radiators.
This fault is frequently seen in autumn when homeowners turn their heating back on for the first time after summer, revealing pressure drops or small leaks that developed while the system was idle.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open the small valves at either end of the hose until you hear water flowing.Watch the pressure gauge until it reaches between 1 and 1.5 bar, then close both valves tightly.
Find a Gas Safe engineer
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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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