BoilerFaultCodesWhat the manual says
Manufacturer manualSafety switch-off: Temperature rise too fast. Pump blocked, insufficient pump output, air in product, system pressure too low, non-return valve blocked/incorrectly installed
Shared across the ecoTEC plus range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 72 fault codes on the ecoTEC plus 418 VU 186/6-5
Seeing a different code? Every code this model can display, in one place.
Related guides you might find useful
Hot water works but heating does not
On a combi it is usually the diverter valve. On a system boiler, the motorised valve.
Read →What pressure should my boiler be?
1 to 1.5 bar when cold on most UK boilers, from the manuals.
Read →Banging, kettling or whistling noise
Each noise points to a different fault.
Read →