BoilerFaultCodesWhat the manual says
Manufacturer manualMaximum 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.
From this model's manual
Verified against the Atag/Atag Q 30cr 4131010 installation & service manual, page 39.
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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Related fault codes
All 29 fault codes on the Q 30CR
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