Medium
Block 11 on Atag Q 30CR

Your boiler has paused the heating because it cannot move water through your radiators fast enough, likely due to a blockage or closed valves.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Maximum ΔT of flow and return sensor in central heating has repeatedly been exceeded. During the block normal operation of the hot water supply is possible. The pump continues to operate at minimum capacity during the block.

DIY fix possible

Check that all radiator valves throughout your home are fully open.Ensure your system pressure is set correctly, usually between 1.0 and 1.5 bar.Check for any signs of a stuck pump or sludge buildup in the system pipes.

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