BoilerFaultCodesTechnical description
No Water Flow
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't circulating through the unit quickly enough to carry heat away safely. The most common reasons include a failing internal pump, a physical blockage in the pipework, or air trapped within the system preventing the flow of water.
This issue is more frequent in autumn when heating systems are turned back on after a summer of inactivity, which can cause the internal pump 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.
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