Medium
Err.4 on Atag Q 30CR

Your boiler is displaying a memory code that simply records the last fault it experienced, meaning the main underlying issue needs to be diagnosed.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

What the manual says

Manufacturer manual

Last predecessing error

From this model's manual
Verified against the Atag/Atag Q 30cr 4131010 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

Err.1View →Err.2View →Err.3View →

All 29 fault codes on the Q 30CR

Seeing a different code? Every code this model can display, in one place.

Block 01Block 11Block 12Block 60Block 67Block 80Block 81Block 82Block 85C123Err.1Err.2Err.3Err.5Err.LError 00Error 01Error 02Error 04Error 05Error 12Error 18Error 19Error 28Error 69Error 80FILLHIGH

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