Technical description
Hot water circulation pump
What causes this fault?
This fault occurs when the boiler's internal pump fails to spin, meaning heated water cannot be moved toward your radiators or hot water tank. The most common reason is that the pump has become physically seized by a buildup of sludge or debris, or the electrical components inside the pump have reached the end of their lifespan.
This issue is frequently seen in autumn when the heating is turned back on for the first time after being idle all summer, which allows debris to settle and seize the pump.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.