154
FAULT CODE
ATAG
Return Temperature Higher Than Flow / Rapid Rise
Medium Severity
Engineer Required
The return temperature is greater than the flow temperature, or the flow temperature is rising too fast. Indicates reversed connections or circulation fault.
Step-by-Step Fix Guide
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Step 1
Check system pressure and bleed radiators
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Step 2
Check that flow and return pipes are correctly connected
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Step 3 Engineer only
Call a Gas Safe engineer if fault persists
Gas Safe Reminder
Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.