BoilerFaultCodes.com

Worcester Bosch Greenstar 24i Junior Fault Codes

Combi Natural Gas 24 kW 2005-2013 Discontinued
GC Number: 47-114-53

Replaced by: Greenstar 25i

This boiler uses indicator light combinations

Note which lights are on, off, or flashing and at what speed. Match the combination to the table below. Do not reset until you have noted the pattern. How to read fault codes →

Most common fault codes

Blue mains indicator light flashing
Your boiler has detected a problem and has stopped working to prevent damage, requiring a simple reset to see if it clears the error.
May be DIY safe · £100-350
BLUE power indicator (B) and reset button (E) flashing alternately
Your boiler is failing to light the gas burner, which means you currently have no heating or hot water.
May be DIY safe · £100-£350
Fast flash / Flashing
Your boiler has detected a internal problem with its electronic control system and has stopped running for safety.
Gas Safe engineer required · £250-450

All 16 fault codes

Code Severity Plain English
2 pulses / No light Low Your boiler isn't broken; it has simply been left in a manual 'service mode' typically used by engineers, and just needs to be switched back to normal operation.
2 pulses No light Low Your boiler is currently stuck in a manual testing mode used by engineers and is not actually broken.
5 pulses / No light Low Your boiler has been accidentally put into a testing mode and simply needs to be switched back to its normal operating setting.
5 pulses No light Low Your boiler is simply in a testing mode used by engineers and is not actually reporting a breakdown or safety fault.
Blue mains indicator light flashing High Your boiler has detected a problem and has stopped working to prevent damage, requiring a simple reset to see if it clears the error.
BLUE power indicator (B) and reset button (E) flashing alternately High Your boiler is failing to light the gas burner, which means you currently have no heating or hot water.
Fast flash / Flashing High Your boiler has detected a internal problem with its electronic control system and has stopped running for safety.
Fast flash / Off High Your boiler has experienced a serious software or electrical error and has locked itself for safety, meaning it cannot provide heat or hot water.
Fast Flashing High Your boiler's main internal computer has developed a serious error and can no longer control the heating system safely.
Indicator light flashes fast (constant interval) High Your boiler has detected a general internal fault and has locked itself out to prevent damage or safety issues.
Indicator light flashes slow (constant interval) High Your boiler has detected a general internal fault and has stopped working to prevent damage or safety issues.
Indicator light flashes slow/fast (uneven interval) High Your boiler has detected a general fault that has caused it to stop working for safety reasons.
Off / Off High Your boiler has completely lost power and its display screen is blank, meaning it cannot operate or heat your home.
On / Off Medium Your boiler is providing hot water as normal, but there is a communication issue preventing the heating from turning on when you use your thermostat.
Slow flash (normally off, flashes on) / Flashing (reset required) High Your boiler has tried to light several times but failed, so it has shut itself down for safety.
Slow flash (normally on, flashes off) / Flashing (reset required) High Your boiler has detected that the exhaust gases are getting too hot and has shut down as a safety precaution to prevent damage.

Worcester Bosch Greenstar 24i Junior is discontinued — time for a new one?

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

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