Main Eco Fault codes & diagnostics

0 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Natural Gas 25-30 kW 2005-2012 Discontinued
GC Numbers 47-467-0147-474-0347-467-03

Replaced by: Main Eco Compact

Download the Main Eco manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Versions & GC numbers

Which version do you have?

The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.

GC number Appliance (register name) Produced
47-467-01 Combi 25 Eco 2008–2012
47-474-03 Combi 30 HE 2005–2012
47-467-03 Combi 30 Eco 2008–2012

Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.

Status & diagnostic codes

10 operating states & engineer diagnostics

Not faults — these are normal operating states. Tap to expand.

24 Status Your boiler has stopped working because it cannot light its flame, which is sometimes caused by a blockage in the pipe that drains away waste water. 25 Status Your boiler has detected that it is getting dangerously hot and has automatically shut itself down to prevent damage or fire risk. 26 Status Your boiler is struggling to clear exhaust gases outside, so it has safely shut itself down to prevent any risk of fumes entering your home. 27 Status Your boiler is struggling to circulate water, either because there isn't enough water inside the system or because the internal pump has failed. 28 Status Your boiler is struggling to detect the temperature of the water coming out of your taps, which means it cannot heat your hot water properly. 29 Status Your boiler has stopped working because it is unable to accurately measure the temperature of the water used for your radiators. 30 Status Your boiler is simply performing its normal startup routine after being switched on or restarting after a power cut. 31 Status Your boiler is currently running in hot water mode, which is a standard operating state rather than a breakdown. 32 Status Your boiler is currently stuck in a cycle while trying to heat your radiators, which means your heating and hot water may not work until the issue is cleared. 33 Status Your boiler is operating normally and the burner is currently lit, meaning it is successfully heating your water or radiators.