BoilerFaultCodesTechnical description
Poor circulation
What causes this fault?
This fault occurs when the boiler detects that water is not flowing through the internal pipework quickly enough to carry heat away. The most common reasons are a pump that has seized up or a build-up of sludge and debris that is physically blocking the narrow passages inside the main heat exchanger.
This issue often surfaces in autumn when the heating is turned back on after a long summer break, as stagnant debris can settle and cause the 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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