BoilerFaultCodesYour boiler is failing to circulate water when you turn on a hot tap, meaning you will likely have no hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump does not run when domestic hot water demand is active
What causes this fault?
This fault occurs when the boiler detects that water isn't moving through the internal tank even though you have turned on a hot tap. The most common reason is a seized or failing internal pump, but it can also be caused by a faulty flow sensor that fails to tell the boiler to start the heating process.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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
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