BoilerFaultCodesTechnical description
The boiler is in domestic hot water (DHW) mode
What causes this fault?
This code appears when the boiler's internal sensors detect a demand for hot water from a tap or shower. It is a normal operational signal indicating that the burner is firing specifically to heat your water rather than your radiators. Once you turn the tap off, the code will disappear as the boiler returns to its standby or heating mode.
DIY fix possible
Check that your hot water taps are fully turned offOnce the tap is closed, wait a few moments for the code to disappear and the boiler to return to standby or heating modeIf the code stays on when all taps are off, you may have a dripping tap or a minor leak in the hot water pipework
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