BoilerFaultCodesYour boiler has detected that the water is not moving through the system quickly enough before the burner fires up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pre-Circulation Fault
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't flowing through the heat exchanger as fast as it should. The most common reasons are a failed or sticking pump, air trapped within the system, or a blockage caused by a buildup of sludge and debris.
This issue is more frequent in autumn when the heating is turned on for the first time after summer, as pumps can seize during long periods of inactivity.
DIY fix possible
Check that your boiler pressure is between 1 and 1.5 bar on the gaugeEnsure all radiator valves are fully open to allow water to circulateRestart the boiler using the reset button to see if the error clears
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 E193 — no call-out fees, no surprises.
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Potterton Promax Combi HE Plus 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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