BoilerFaultCodesYour boiler has detected that the water pressure is too low for it to operate safely and effectively.
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
What causes this fault?
This fault occurs when the water level inside your central heating system drops below the minimum level required to circulate heat. The most common reasons for this are a leak somewhere in the pipework or radiators, or because the system was recently bled without being topped back up.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time and find the pressure has naturally seeped away over the summer months.
DIY fix possible
Locate the filling loop (the silver braided hose) underneath or near the boilerSlowly open the tap or taps on the filling loop to allow water into the systemMonitor the pressure gauge and close the taps firmly once it reaches 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 H — 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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