16 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 |
|---|---|---|
| 47-311-82 | Greenstar Highflow 440 | 2004–2008 |
| 47-311-83 | Greenstar Highflow 440 | 2004–2008 |
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.
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Your boiler is having trouble reading the temperature of its built-in hot water storage tank, which usually means it will temporarily stop heating your water.
Your boiler has detected an internal communication failure between its main electronic circuit boards, meaning it has temporarily stopped working for safety reasons.
Your boiler is having trouble measuring the temperature of your hot water, which usually means it cannot safely heat water for your taps right now.
Your boiler has detected an internal electronic failure within its main control module, meaning it has safely shut down to prevent further issues.
Your boiler's computer memory chip is loose or missing, meaning the system doesn't know which model it is and has stopped working for safety.
Your boiler has stopped working because the internal fan, which clears exhaust gases, isn't spinning fast enough to operate safely.
Your boiler has temporarily stopped working because a vital safety connection inside the unit has become loose or disconnected.
Your boiler has temporarily stopped working because the internal pump responsible for safely draining wastewater cannot do its job.
Your boiler has temporarily stopped working because the built-in hot water storage tank has become too hot.
Your boiler has temporarily stopped working because it cannot properly read the temperature of the water flowing through the heating system.
Your boiler has temporarily shut down because the internal temperature became too high, acting as a vital safety measure to prevent damage.
Your boiler is failing to light the gas or isn't detecting that the flame has started, causing the system to shut down for safety.
Your boiler's internal computer has encountered a critical electronic software or hardware error that is preventing it from running safely.
Your boiler's internal safety system has detected a flame or a false flame signal when the heating or hot water should be switched off.
Your boiler has sensed a flame after the gas supply was shut off, which is a safety precaution that requires a professional engineer to investigate.
Your boiler has been put into a temporary reset mode because the button was held down too long or pressed accidentally.
BoilerFaultCodes