BoilerFaultCodes.com

Vaillant ecoTEC Pro Fault Codes

Combi Natural GasLPG 24-30 kW 2012-present
GC Numbers: 47-044-5147-044-5247-047-36

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Most common fault codes

F.00
Your boiler has lost connection with its internal thermometer, meaning it cannot safely tell how hot the water is and has shut down as a precaution.
Gas Safe engineer required · £90-160
F.01
Your boiler has stopped working because it cannot communicate with the sensor that monitors the temperature of the water returning from your radiators.
Gas Safe engineer required · £90-160
F.10
Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water leaving the unit, causing it to shut down for safety.
Gas Safe engineer required · £100-£180

All 39 fault codes

Code Severity Plain English
F Low Your boiler is not currently experiencing an active fault; you have simply accessed the internal menu used by engineers to view the history of previous error codes.
F.00 High Your boiler has lost connection with its internal thermometer, meaning it cannot safely tell how hot the water is and has shut down as a precaution.
F.01 High Your boiler has stopped working because it cannot communicate with the sensor that monitors the temperature of the water returning from your radiators.
F.10 High Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water leaving the unit, causing it to shut down for safety.
F.11 High Your boiler has stopped working because a internal sensor that monitors the temperature of the water returning to the unit has developed an electrical fault.
F.20 High Your boiler has shut itself down because it has detected that it is getting far too hot, usually due to a lack of water flow or a circulation blockage.
F.22 High Your boiler has switched itself off because the water pressure has dropped too low to operate safely.
F.23 High Your boiler has shut down because water isn't moving through the system quickly enough, causing it to overheat too rapidly.
F.24 High Your boiler has shut down because it is heating up much faster than it can circulate the water, usually due to a blockage or a pump issue.
F.25 High Your boiler has shut down automatically because it detected that the exhaust gases are getting too hot, which is a safety feature to prevent damage to the internal components.
F.26 High Your boiler is unable to release gas into the burner because the internal electronic valve is not operating correctly, meaning it cannot ignite to provide heat or hot water.
F.27 High Your boiler has detected a flame when there shouldn't be one, which has caused it to shut down for safety purposes.
F.28 High Your boiler is unable to light the gas to produce heat, meaning your heating and hot water will not work.
F.29 High Your boiler has lost its flame while running and is unable to automatically restart, likely because the gas flow is being interrupted.
F.32 High Your boiler has detected an issue with the fan that helps clear exhaust gases, causing the system to shut down for safety.
F.49 High Your boiler is struggling to send signals between its internal components because the communication line has a low electrical voltage.
F.61 High Your boiler is unable to send gas to the burner because of a communication failure between the main control board and the gas valve.
F.62 Emergency Your boiler is failing to shut off the gas properly at the end of a heating cycle, which is a safety issue requiring professional inspection.
F.63 High Your boiler’s internal computer chip has suffered a memory error, preventing it from processing the instructions needed to run your heating.
F.64 High Your boiler's computer has detected a conflict between its internal sensors or a wiring fault, causing it to shut down for safety.
F.65 High Your boiler's internal control board has overheated or suffered an electrical failure, causing the system to shut down to prevent damage.
F.67 High Your boiler's computer has detected a flame when it shouldn't be there, or is confused by an electrical signal from the burner area.
F.68 High Your boiler is struggling to keep its flame steady, which is preventing it from staying on and heating your home.
F.70 High Your boiler's main control board has lost its identity or is communicating incorrectly with the display unit, often following a part replacement.
F.71 High Your boiler's internal thermometer is reporting a temperature that doesn't make sense, causing the system to shut down for safety.
F.72 High Your boiler has detected that the two pipes measuring temperature are giving very different readings, which usually means a sensor is failing or there is a blockage in the system.
F.73 High Your boiler's internal sensor is struggling to detect the correct water pressure levels, which is preventing the system from running safely.
F.74 High Your boiler has detected that the water pressure is too high, which has caused it to stop working to protect the internal components.
F.75 High Your boiler is struggling to detect a rise in water pressure when the pump starts up, which is preventing it from firing for your heating or hot water.
F.77 High Your boiler has stopped working because it cannot properly drain away waste water or there is a blockage in the ventilation system.
F.78 High Your boiler is confused because it is looking for a hot water sensor that is either missing or has a broken connection, preventing it from heating your water correctly.
F.83 High Your boiler is struggling to detect a proper temperature change between the pipes, which usually means there is not enough water moving through the system to heat your home properly.
F.84 High Your boiler is confused because the temperature sensors measuring water going out and coming back are giving contradictory or swapped readings.
F.85 High Your boiler has detected that the temperature sensors are giving unusual readings, likely because they are loose or have been installed on the wrong pipes.
F.92 High Your boiler has detected that the fuel type it is being supplied with does not match its internal settings, causing it to shut down for safety.
P.00 Low Your boiler is simply running a self-cleaning routine to remove trapped air from the system and is not actually at fault.
P.01 Low Your boiler is currently running a professional test mode used to check its performance at full power.
P.02 Low Your boiler is performing a routine self-diagnostic purge or testing phase and is not currently experiencing a breakdown.
P.06 Low Your boiler has been manually set to a maintenance mode for filling or draining the system, meaning it is currently paused and will not provide heating or hot water.

Status & diagnostic codes

These codes indicate your boiler's operating state or a diagnostic reading — not necessarily a fault. Status codes (S.) mean normal operation; diagnostic codes (D.) are informational readings used by engineers.

Code Type Description
D.002 Diagnostic This is a temporary pause where the boiler rests for a few minutes to prevent any unnecessary wear and tear from switching the burner on and off too frequently.
D.014 Diagnostic This is a technical setting that controls how fast your boiler's internal pump circulates water throughout your heating system.
D.084 Diagnostic This is a scheduled service reminder notification showing that your boiler is due for its routine professional maintenance check.
S.00 Status Your boiler is currently idle because it has not received a signal from your thermostat or timer to turn the heating on.
S.01 Status Your boiler is currently preparing to provide heating and is going through its normal start-up cycle.
S.02 Status Your boiler is simply completing a brief self-check and starting the pump before it begins heating your radiators.
S.03 Status Your boiler is currently trying to light the flame to start your heating, which is a normal part of its startup sequence.
S.04 Status Your boiler is currently working as it should and is providing heat to your radiators.
S.05 Status Your boiler is currently taking a short pause to circulate water and cool down internal parts after a period of heating.
S.06 Status Your boiler is simply cooling itself down after providing heating and will return to normal operation shortly.
S.07 Status Your boiler is simply cooling itself down after finishing a heating cycle and does not require any action.
S.08 Status Your boiler has temporarily paused its burner to prevent it from switching on and off too frequently, which helps protect the components and save energy.
S.10 Status Your boiler is simply letting you know that it has detected you have turned on a hot tap and it is currently working to heat your water.
S.11 Status Your boiler is simply preparing to heat your tap water and is currently checking that its internal fan is spinning correctly before firing up.
S.13 Status Your boiler is currently trying to light the flame to provide hot water for your taps or shower.
S.14 Status Your boiler is working normally and is currently firing up to provide hot water to your taps or shower.
S.15 Status Your boiler is simply taking a moment to cool itself down after heating your water, which is a normal part of its operation.
S.16 Status Your boiler is briefly keeping the fan running after you have used hot water to safely clear away any remaining heat and gasses.
S.17 Status Your boiler is simply running the pump for a short time after you have used hot water to cool the internal components down safely.
S.20 Status Your boiler is simply letting you know that someone has turned on a hot tap or a shower and it is currently working to heat that water.
S.21 Status Your boiler is currently preparing to supply hot water and is in a normal sequence of starting up its internal fan.
S.22 Status Your boiler is briefly preparing itself to provide hot water and this status code is a normal part of its operation.
S.23 Status Your boiler is simply going through its normal process of lighting the burner to provide you with hot water.
S.24 Status Your boiler is simply indicating that it is currently firing up to provide hot water to your taps or shower.
S.25 Status Your boiler is briefly keeping its internal parts running to safely cool down after you have finished using your hot water.
S.26 Status Your boiler is briefly cooling itself down after providing hot water and should return to normal operation shortly.
S.27 Status Your boiler is briefly running the internal pump after you have finished using hot water to safely move heat away from the system.
S.28 Status Your boiler is taking a brief programmed break to prevent it from turning on and off too quickly while heating your hot water.
S.30 Status Your boiler is working fine but is currently waiting for your thermostat or timer to tell it to turn on.
S.31 Status Your boiler is currently set to 'Summer Mode', meaning the heating is switched off while hot water remains available.
S.32 Status Your boiler is temporarily pausing because the fan is having trouble reaching or maintaining the correct speed to start the ignition process safely.
S.34 Status Your boiler has noticed the temperature is very low and is running briefly to prevent the internal pipes from freezing.
S.39 Status Your boiler has shut down because it has detected an issue with a safety sensor or the pump that removes excess water from the system.
S.40 Status Your boiler is temporarily running at a lower power level to prevent a fault and ensure it can still provide some warmth while it detects a minor issue.
S.41 Status Your boiler has detected that there is too much water in the system, causing the internal pressure to rise above safe operating levels.
S.42 Status Your boiler has stopped working because it has detected a blockage in the exhaust system or a failure in the pump that removes waste water.
S.46 Status Your boiler has noticed an unstable flame when running at its lowest setting and is operating at a restricted level to prevent a complete breakdown.
S.53 Status Your boiler has temporarily paused because water is not moving through the system fast enough to take the heat away safely.
S.54 Status Your boiler has paused operation because it has detected a lack of water flow or pressure, preventing the system from heating up safely.
S.57 Status Your boiler is temporarily pausing to perform a routine internal diagnostic check and will resume normal operation on its own shortly.
S.58 Status Your boiler has temporarily restricted its power output to protect itself, often while it waits for water temperatures to balance out.
S.61 Status Your boiler has detected that its internal safety settings don't match the type of gas being supplied to the property, causing it to stop running for safety.
S.62 Status Your boiler is struggling to burn gas correctly and efficiently, which can lead to it locking out to ensure safety.
S.63 Status Your boiler has detected a potential blockage or issue with the gas supply or internal gas valve, causing it to shut down for safety.
S.76 Status Your boiler is warning you that the water pressure is getting too low to operate efficiently, though it may still be working for now.
S.88 Status Your boiler is currently running an automatic air removal process to clear bubbles from the system and does not require a repair.
S.92 Status Your boiler is currently running a routine internal check to ensure there is enough water flowing through the system to operate safely.
S.93 Status Your boiler is struggling to accurately check the quality of its exhaust gases, which is preventing it from completing its ignition cycle safely.
S.96 Status Your boiler is currently running a background check on its internal temperature readings to ensure they are accurate before it starts up.
S.97 Status Your boiler is performing a routine internal check on its water pressure sensor and should resume normal operation once finished.
S.98 Status Your boiler is currently running a brief automatic check on its temperature sensors and should return to normal operation shortly.
S.99 Status Your boiler is simply performing a routine internal check-up to ensure everything is working correctly and will resume normal operation shortly.

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