BoilerFaultCodes
Atag Boiler Fault Codes
450 fault codes across 14 Atag boiler models — explained in plain English.
Dutch premium heating manufacturer. High efficiency products for the UK market.
Just want the most common Atag problems?
The top 8 faults across the whole Atag range — causes, DIY checks, repair costs.
High-severity Atag fault codes
FILL HIGH Block 01 Block 60 Block 80
Your boiler has automatically stopped working because the water pressure inside your heating system has dropped too low.
Q 25CR
Your boiler has detected that the water pressure inside your heating system is too high and has safely shut itself down to prevent damage.
Q 25CR
Your boiler has detected that an external safety device, such as a heat sensor or chimney flue thermostat, has triggered a shutdown to prevent overheating or unsafe operation.
Q 25CR
Your boiler's internal settings have been incorrectly configured, preventing it from safely regulating its power output.
Q 25CR
Your boiler has automatically paused itself because the waste gases exiting the flue are dangerously hot, likely indicating an internal system blockage or a failed sensor.
Q 25CR
All models
14 Atag boiler models
Q 25CR
CombiSystem Discontinued
Q 30CR
CombiSystem Discontinued
S 25CR
System Discontinued
E22c
CombiSystem Discontinued
Premier
Combi Discontinued
Q 25S
CombiSystem Discontinued
A200
CombiSystem Discontinued
E Range
CombiSystem Discontinued
E32S
System Discontinued
Sov.
System Discontinued
iC Economiser Plus
Combi
iS System
System Discontinued
iR Regular
Regular Discontinued
iC28
Combi
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