95 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 |
|---|---|---|
| 47-044-67 | ecoTEC plus 630 VU GB 306/5-5 | 2005–2015 |
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 has lost its connection to an internal temperature sensor, meaning it cannot accurately read how hot it is.
Your boiler has lost the temperature reading from one of its internal sensors, meaning it cannot safely regulate heat and has temporarily shut down.
Your boiler has temporarily stopped working because it has detected a faulty temperature sensor connection linked to its internal hot water storage cylinder.
Your boiler has detected a faulty temperature sensor connection, which usually stops it from working safely.
Your boiler has detected a faulty temperature sensor or a wiring problem, meaning it cannot accurately measure how hot the water is.
Your boiler has detected a faulty temperature sensor or a wiring issue, which means it cannot accurately measure how hot the water is and has stopped working for your safety.
Your boiler has detected a faulty temperature sensor and a possible wiring issue, which will cause it to shut down to prevent damage.
Your boiler has detected a sensor wiring fault relating to its hot water temperature monitoring.
Your boiler has safely shut down because it has detected an electrical safety issue or a faulty temperature sensor inside the unit.
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
Your boiler has stopped working because water is not flowing properly through it, which is usually caused by trapped air, a stuck pump, or incorrect pipe connections.
Your boiler has stopped working because water is not flowing properly through it, usually due to trapped air or low system pressure.
Your boiler has temporarily stopped working because it has detected a loose electrical connection or safety sensor issue related to the exhaust flue.
Your boiler has detected an issue with the valve that controls the gas supply, meaning it cannot safely ignite to provide heating or hot water.
Your boiler has detected moisture or a false flame signal inside the unit and has safely locked itself out to prevent unsafe operation.
Your boiler is failing to light because it cannot detect a successful flame or is not receiving enough gas to start up.
Your boiler has tried to start up several times but failed to ignite, usually because the gas supply has been temporarily interrupted or the system cannot clear exhaust gases properly.
Your boiler has detected an issue with the internal fan that safely removes combustion gases, causing it to lock out for safety.
Your boiler has detected an issue with the airflow or flue system, meaning it cannot safely remove combustion gases and has temporarily stopped working.
Your boiler has detected a blockage or restriction in the pipe that brings in fresh air and removes exhaust gases.
Your boiler has detected an internal configuration issue with the fuel type settings on its main computer board, which requires professional calibration.
Your boiler has detected an electrical communication problem in its internal wiring control system, causing it to shut down to protect its internal electronics.
Your boiler has detected an issue with its internal gas sensor or combustion system and has temporarily locked itself out to keep your home safe.
Your boiler has detected high levels of carbon monoxide inside its casing and has safely shut itself down to protect your home.
Your boiler has detected that an internal component used for safe ignition has become worn or corroded over time.
Your boiler has detected an issue with the internal valve that controls the gas supply, meaning it cannot safely ignite.
Your boiler has detected an issue with the gas valve not shutting off properly when it should, which requires a Gas Safe registered engineer to inspect for safety.
Your boiler's main computer control panel has suffered a critical internal memory failure and can no longer process instructions to run your heating system.
Your boiler has detected a sudden reading error from one of its internal temperature sensors, causing it to lock out for safety.
Your boiler has detected that its internal computer is running too hot and has safely shut down to prevent permanent damage.
Your boiler has temporarily stopped working because the internal computer is receiving a confusing signal from the flame sensor.
Your boiler is locking out because the flame inside is flickering or going out unexpectedly, which usually points to an issue with the gas supply, air flow, or waste pipe blockage.
Your boiler's computer system is confused because internal identification numbers were not properly set up after a recent repair.
Your boiler has temporarily stopped working because a sensor that measures water temperature is giving a faulty reading.
Your boiler has detected an unusual temperature difference between the water leaving it and the water returning to it, usually due to a faulty reading from the internal sensors.
Your boiler's water pressure sensor is failing to communicate properly, which usually means the sensor itself is faulty or has a loose wire.
Your boiler has detected an electrical fault with the internal water pressure sensor, which means it cannot accurately read the system pressure and has stopped working as a safety precaution.
Your boiler has detected low water pressure or a circulation issue, meaning it cannot safely run the heating or hot water.
Your boiler has detected an issue with the system that safely removes waste gases or water, meaning it has temporarily stopped working for your safety.
Your boiler has registered a wiring configuration error related to the hot water sensor when an external control or link box is fitted.
Your boiler has detected a faulty temperature sensor inside its hot water storage cylinder, meaning it may struggle to provide reliable hot water.
Your boiler is struggling to pump hot water to your cylinder, which means your stored hot water is not heating up properly.
Your boiler has detected an electrical fault with a special component inside the hot water cylinder that prevents corrosion, meaning it is either unplugged or damaged.
Your boiler has detected that the water inside is not heating up as quickly as expected when the burner tries to start.
Your boiler has detected an unexpected difference in temperature between its internal pipes, usually because the main sensors are misread, incorrectly installed, or mixed up.
Your boiler has detected an internal sensor installation error, meaning the temperature monitoring components are incorrectly positioned or wired.
Your boiler is temporarily confused and has lost internal communication with one of its connected water storage modules.
Your boiler has detected a problem with water flow and pressure sensors, meaning it cannot circulate water safely and has shut down your heating and hot water.
Your boiler is currently running a routine diagnostic check to test its internal systems and settings.
Your boiler has successfully detected a request for hot water and is starting up normally.
Your boiler is currently preparing to fire up by starting its internal fan, which is a normal part of the ignition process.
Your boiler is struggling to light its flame, which means you may experience intermittent issues with your heating and hot water.
Your boiler is currently operating normally and is heating water for your taps or shower.
Your boiler is simply finishing a cooling cycle after you have used the hot water taps, which is a normal part of its operation.
Your boiler has detected an issue with the air fan system and has temporarily stopped heating to prevent further damage.
Your boiler is currently just running its internal pump to move residual heat away from the heat exchanger after a hot water cycle, which is a normal part of its operation.
Your boiler is currently running a brief internal testing sequence to check hot water settings and will return to normal operation by itself.
Your boiler is simply detecting that someone has turned on a hot tap and is preparing to heat the water for you.
Your boiler is currently going through its normal starting sequence to begin heating your water.
Your boiler is simply preparing the water pump before sending hot water to your taps, which is a normal part of its startup routine and not actually an error.
Your boiler is currently struggling to light the flame it needs to provide heating and hot water.
Your boiler is currently operating normally and is in the process of heating your radiators.
Your boiler is currently just finishing a routine cooling-down process after providing hot water and should return to normal operation shortly.
Your boiler's fan is attempting to spin, but the electronic control board isn't receiving the correct signal back to confirm it is working properly.
Your boiler is simply finishing its cooling cycle after providing hot water and is operating exactly as it should.
Your boiler is temporarily pausing between hot water cycles to protect itself from overheating and wear.
Your boiler is currently running an internal testing procedure for your hot water system and is not actually broken.
Your boiler is temporarily paused because your wall thermostat or heating controller is telling it not to send heat to your radiators.
Your boiler is simply resting because your heating controls are currently switched off or set to summer mode, meaning no heat is needed right now.
Your boiler is temporarily paused because the internal fan isn't spinning at the correct speed to safely clear exhaust fumes.
Your boiler is temporarily pausing its operation because it has detected a drop in the internal airflow pressure.
Your boiler has temporarily fired up its internal frost protection system to prevent the pipes from freezing during cold weather.
Your boiler has temporarily blocked heating mode because the room thermostat or smart controller is currently set to an invalidly low temperature.
Your boiler has temporarily paused because it detected a problem with the internal fan that safely pushes harmful gases out of your home.
Your boiler has temporarily paused heating because a safety switch, such as the one connected to your condensate drain pump, has triggered to prevent a water overflow.
Your boiler has detected a minor performance issue and is operating in a temporary energy-saving mode to ensure it keeps running safely while limiting output.
Your boiler has detected that the water pressure is too high, often caused by the filling loop being left open or a fault in the expansion system.
Your boiler has paused its heating because a safety sensor has detected a potential blockage in the waste water removal or the exhaust safety flap.
Your boiler has temporarily lowered its heating output to prevent the flame from going out completely, usually due to a minor combustion issue.
Your boiler has temporarily paused to protect itself because the water is not flowing properly between the pipes, usually due to low pressure or trapped air.
Your boiler has temporarily paused to protect itself because the water pressure inside is too low, or water isn't flowing properly through the system.
Your boiler is temporarily pausing its operation to allow its internal safety sensor to check the air quality before it starts up again.
Your boiler has temporarily paused its operation because it detected high levels of combustion byproducts, and it is waiting safely until it is clear to try again.
Your boiler has temporarily paused because an internal self-check didn't finish properly, but it has switched to a backup mode to keep you warm while it waits to try again.
Your boiler has temporarily reduced its power because it is detecting unusual air movement or wind pressure in the flue system, likely due to external weather conditions.
Your boiler has paused because the flow of water moving through the system has dropped too low to operate safely.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is reminding you that its internal water flow sensor needs a routine check or service.
Your boiler is currently running an automatic program to clear air bubbles out of the internal pipework and does not require a repair.
Your boiler is currently running a routine check of the water flow inside the system to ensure it is operating safely and effectively.
Your boiler is temporarily running through a routine check of its exhaust gases, so you just need to wait a few moments for it to finish.
Your boiler is performing a routine diagnostic test on its internal temperature sensors, which temporarily pauses the heating.
Your boiler is currently running a brief self-test on its water pressure system and temporarily pausing heating until the check is complete.
Your boiler is temporarily running a self-test on its internal temperature sensors, which pauses your heating until the check is finished.
Your boiler is simply running through its routine internal system check and does not indicate a fault.
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BoilerFaultCodes