BoilerFaultCodesYour boiler has lost water pressure and has stopped working to protect itself from damage.
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 low / No water in boiler
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below a safe level, causing the boiler to shut down to prevent internal overheating. The most common reason is a slow leak somewhere in your radiators or pipework, or a failing component like the expansion vessel that can no longer manage pressure changes.
This issue often surfaces when you first turn the heating back on for autumn, as the sudden increase in heat and pressure can expose small leaks or weakened seals that occurred during summer.
DIY fix possible
Locate the filling loop (the silver flexible hose) usually found underneath or near the boiler.Slowly open the one or two taps on the hose while watching the pressure gauge.Close the taps firmly once the pressure gauge reaches between 1.0 and 1.5 bar.
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 E10 — no call-out fees, no surprises.
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Potterton Powermax HE is discontinued — time for a new one?
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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