BoilerFaultCodesYour boiler has lost water pressure, which means there isn't enough water in the system to keep it running safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: All Boilers
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below a safe operating level. The most common reasons are a slow leak in the pipework or radiators, or air being released from the system through the vents. It can also happen if you have recently bled your radiators and haven't topped the water level back up.
This issue is more common in autumn when homeowners turn their heating back on for the first time, as small leaks or air pockets often develop during months of inactivity.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open the one or two taps/valves on the loop until you hear water flowing.Watch the pressure gauge and close the valves once the needle 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 118 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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