BoilerFaultCodesTechnical description
No CH or No CH1 Pump
What causes this fault?
This fault occurs when the boiler's internal computer detects that the central heating pump is either completely stuck or not communicating properly. The most common reason is that the pump has seized due to a buildup of debris in the system water or an electrical failure within the pump's motor. Without this component spinning, the boiler cannot move hot water to your radiators and must shut down to prevent overheating.
This issue is frequently seen at the start of autumn when heating systems are turned on for the first time after being inactive all summer, which can cause internal pump components to seize.
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.