S.27 Low
Your boiler is briefly running the pump after heating your water to cool down the internal components and prevent them from overheating.
Technical description: DHW mode – pump overrun
Typical repair cost: £0 (including labour)
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Protect yourself from future repair bills
A boiler cover plan would cover faults like S.27 — no call-out fees, no surprises.
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