BoilerFaultCodesYour boiler is simply performing a routine internal check as it starts up and the code should disappear after a few seconds.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Part of the self-test sequence sequence when switching on the appliance
What causes this fault?
This code appears when the boiler is first powered on or restarted, serving as a sign that the internal control board is running a diagnostic check. It occurs as the software verifies that all safety sensors and electronic components are communicating correctly before allowing the burner to light. It is not a malfunction, but rather a necessary step in the appliance's normal startup routine.
DIY fix possible
Wait for 30-60 seconds to see if the code clears automaticallyEnsure the power supply to the boiler is stableReset the boiler if the code remains on the screen for more than 2 minutes
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 P6 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Worcester Bosch 29 HE Conventional 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.
Affiliate links — we may earn a commission at no extra cost to you.