BoilerFaultCodesYour boiler has detected that there is not enough water in the central heating system to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No or low system water pressure. system pressure less than 0.5bar
What causes this fault?
This fault occurs when the internal pressure sensor detects that the water level inside your heating system has dropped below a safe operating limit. The most common reason is a slow leak from a radiator valve or pipework, though it often happens after you have bled your radiators and haven't topped the pressure back up.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to remove air pockets.
DIY fix possible
Locate the filling loop (the flexible silver hose) underneath your boiler.Slowly open the one or two taps on the loop until you hear water flowing.Watch the pressure gauge until it reaches 1.5 bar, then close the taps 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 E.02 – .07 — 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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