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: Water pressure switch error – not operated.
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 overheating. The most common reason is a small leak in the pipework or radiators, though it can also happen if you have recently bled your radiators and haven't topped the water back up.
This fault is frequent in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
DIY fix possible
Locate the filling loop (the flexible braided hose) underneath or near the boiler.Slowly open the tap or valve(s) on the loop while watching the pressure gauge.Close the tap or valve(s) tightly once the gauge reaches between 1 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 E119 — no call-out fees, no surprises.
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Baxi Platinum 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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