BoilerFaultCodes.com

Viessmann Vitodens 200 Fault Codes

CombiSystem Natural GasLPG 1.9-60 kW 1999-present
GC Numbers: 47-118-0947-118-1047-118-1147-118-0647-118-0747-118-0847-118-1247-118-1347-118-14

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Most common fault codes

0A
Your boiler has detected an issue with the gas pressure or a component failure and has shut down as a safety precaution.
Gas Safe engineer required · £120-£450
0C
Your boiler has shut down because the electrical power coming into it is too weak or unstable to run safely.
Gas Safe engineer required · £100-350
0D
Your boiler has detected an internal communication error and has shut itself down as a safety precaution.
Gas Safe engineer required · £180-450

All 184 fault codes

Code Severity Plain English
0A High Your boiler has detected an issue with the gas pressure or a component failure and has shut down as a safety precaution.
0C High Your boiler has shut down because the electrical power coming into it is too weak or unstable to run safely.
0D High Your boiler has detected an internal communication error and has shut itself down as a safety precaution.
0F Low Your boiler is simply reminding you that it is due for its regular annual service and there is no actual fault with the system.
1A High Your boiler has shut down because it is struggling to discharge exhaust fumes safely or is detecting a significant lack of air flow.
1B High Your boiler has shut down because it is struggling to discharge exhaust fumes safely or is detecting a significant lack of air flow.
1F High Your boiler has stopped working because the burner isn't lighting correctly, likely due to a problem with the internal airflow or the ignition system.
02 High Your boiler has shut itself down as a safety precaution because it has detected an overheating issue within the system.
04 High Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
05 High Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
5B:0 Medium Your boiler has detected that the hot water cylinder is connected directly to the unit, but there is likely a communication error or a faulty sensor preventing it from heating your water correctly.
5B:1 Medium Your boiler is confused about where your hot water tank is located within the system pipework, often due to a setup error or a sensor problem.
06 High Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
6C:0 to 6C:100 Medium Your boiler's internal pump or fan is reporting an incorrect speed setting, which is usually a technical communication error between the internal computer and the parts that move water or air.
6C:100 Medium Your boiler's internal pump for hot water is stuck running at full speed, which usually means there is a communication error or a part is beginning to fail.
6F:0 to 6F:100 Low Your boiler is providing an advisory notification about how much power it is using to heat your hot water, rather than indicating a mechanical breakdown.
6F:100 Medium Your boiler is telling you that it has defaulted to its maximum power setting for heating your hot water because it has encountered a configuration memory error.
07 High Your boiler has detected a sequence error or a flame signal where there shouldn't be one, causing the burner to shut down completely for safety.
7b:0 Low Your boiler is having a communication problem regarding the time settings between its internal control parts.
7b:1 Low Your boiler is having difficulty communicating the correct time to other parts of the heating system or external controls.
7E:0 Low Your boiler has been incorrectly set to a multi-boiler configuration even though it is operating as a single unit.
7E:1 Medium Your boiler system is communicating with multiple other boilers through a shared exhaust pipe, and it has detected a technical configuration error in that connection.
7F:0 High Your boiler has encountered a technical internal error specifically relating to its main electronic control board which is preventing it from running.
7F:1 High Your boiler’s internal control system has encountered a processing electronic fault, meaning it cannot properly communicate with its own internal components.
08 High Your boiler has detected a sequence of ignition or flame detection errors and has shut itself down for safety.
09 High Your boiler has detected a sequence error or a flame signal where there shouldn't be one, causing the burner to shut down completely for safety.
9A Low Your boiler has lost communication with the temperature sensor that monitors the outdoor solar panels or the system collector, meaning it cannot accurately manage heat levels for those components.
9B High Your boiler has lost communication with one of its internal heat sensors, meaning it cannot monitor temperatures accurately to operate safely.
9b:1 to 9b:127 High Your boiler has detected an error with its internal temperature settings or the control unit, which may cause it to stop providing heating or hot water correctly.
9b:70 Low Your boiler has detected an incorrect setting or a communication error regarding the minimum water temperature required when an external control system asks for heat.
9C High Your boiler is unable to read the temperature of your hot water cylinder because the connection to the sensor has been lost or damaged.
9C:0 High Your boiler has stopped working because its internal control computer has lost its configuration settings or is unable to communicate with its safety sensors.
9C:5 to 9C:60 Low Your boiler is currently undergoing a pre-set maintenance test or a specialized calibration check that lasts between 5 and 60 minutes.
9C:20 Medium Your boiler has lost communication with one of its internal control modules or an external smart accessory, causing it to use temporary backup settings.
9F Low Your boiler has lost communication with the solar heating control panel, meaning your solar panels won't be helping to heat your water.
9F:0 to 9F:40 Low Your boiler is notifying you that it has reached a specific temperature difference limit you have set, which usually means the water is heating up faster or slower than expected.
9F:8 Medium Your secondary heating circuit is not reaching the required temperature difference to operate correctly, likely due to a flow or sensor issue in that specific zone.
10 Medium Your boiler is struggling to accurately gauge the weather outside, meaning it might not provide the right amount of heat for your home.
18 Low Your boiler has lost its connection to the outside temperature sensor, meaning it cannot automatically adjust your heating based on the weather.
20 High Your boiler has detected an electrical fault with a sensor that monitors the water temperature flowing into your heating system, leading it to shut down for safety.
25 High Your boiler is getting too hot too quickly and is shutting itself down to prevent damage.
26 High Your boiler's computer has become stuck in a repeating internal test sequence and is failing to move into its normal heating mode.
28 Medium Your boiler has lost connection with a temperature sensor that monitors the main water flow, likely due to a broken wire or a faulty sensor.
30 High Your boiler has stopped heating because a internal sensor that monitors water temperature has developed an electrical fault and is preventing the burner from firing.
34:0 Low Your boiler is receiving a constant request for heat from an external control or thermostat, causing all the pumps to run continuously.
34:1 Low Your boiler is receiving a specific signal from an external control or accessory that it doesn't currently know how to handle.
34:2 Medium Your boiler is receiving a conflicting signal from an external control or accessory that is telling the pumps how to run incorrectly.
35 High Your boiler has failed to ignite or stay lit, meaning your heating and hot water have stopped working.
38 High Your boiler has stopped working because it can no longer accurately measure the temperature of the water inside the system.
38:0 Low Your boiler is reporting a normal status update rather than a failure, indicating that the internal burner control system is currently operating correctly.
40 High Your boiler has stopped working because it thinks the hot water tank is dangerously overheating due to a faulty electrical sensor.
48 High Your boiler has stopped heating your hot water because it can no longer detect the temperature of your hot water cylinder.
50 High Your boiler has stopped providing hot water because the internal sensor that measures water temperature has detected a technical fault or a short circuit.
50:0 High Your boiler's computer screen and main control board are having trouble communicating with each other.
50:1 High Your boiler has detected a short circuit in the sensor that monitors your hot water temperature, meaning it can no longer accurately heat your tap water.
50:3 Low Your boiler is struggling to monitor the temperature outside, which is preventing it from adjusting your heating efficiently.
51 High Your boiler has stopped working because a sensor that monitors the water temperature has developed an electrical fault.
52:0 Medium Your boiler is struggling to monitor the temperature of a specific part of your system's pipework, which may cause your heating to run less efficiently or stop working correctly.
52:1 Medium Your boiler is struggling to accurately measure the water temperature in a specific part of your heating system, which may cause your heating to run inefficiently or not at all.
53:0 High Your boiler has detected a general internal fault that is preventing it from running properly, often linked to an issue with the main control system or a signal error.
53:1 Medium Your boiler has detected a communication problem with the pump that circulates hot water around your taps, which may cause delays in getting hot water or stop it altogether.
53:2 High Your boiler is having trouble communicating with the external pump that circulates hot water to your radiators, meaning your heating may not turn on correctly.
53:3 Medium Your boiler is having trouble communicating with the pump that fills your external hot water tank, meaning your hot water supply may be affected.
54:0 Low Your boiler is confused because it thinks it should be connected to a solar heating system that it cannot find.
54:1 Low Your solar heating system is experiencing a communication error or fault, which may affect how efficiently your water is heated.
54:2 Medium Your boiler is having trouble communicating with the solar heating control module during its automatic setup process.
56:0 Medium Your boiler is experiencing an issue where it cannot properly monitor or control the temperature of your hot water.
56:1 Medium Your boiler's hot water sensor is reporting an unusually high temperature range, which may prevent your hot water from heating correctly.
58 High Your boiler has stopped providing hot water because the internal sensor that measures water temperature is broken or disconnected.
58:0 High Your boiler is struggling to heat your hot water tank because it cannot detect or communicate with a required external sensor or control module.
58:1 to 58:95 Low Your boiler is notifying you that a specific setting for your hot water temperature has been manually adjusted or requested.
59 High Your boiler has stopped working because it cannot accurately measure the temperature of the water leaving the unit, usually due to a fault in a sensor or its wiring.
59:0 Medium Your boiler has detected an issue with the sensors that monitor the temperature of your hot water cylinder, which may lead to inconsistent water temperatures.
59:1 to 59:10 Low Your boiler has detected a minor internal setting inconsistency regarding when it should start heating, but it is unlikely to stop your hot water or heating from working.
60:5 to 60:25 Low Your boiler is struggling to reach the temperature requested for your hot water because the internal settings are set too high or a sensor is misreading.
60:10 Medium Your boiler is getting much hotter than it should while trying to heat your water, which usually means the heat isn't transferring correctly to your tank.
60:20 Medium Your boiler is getting too hot while trying to heat your water, which usually means the heat isn't being transferred to your hot water tank quickly enough.
62:0 High Your boiler's internal pump is failing to stay on long enough to safely dissipate heat after the burner turns off, which can cause the system to overheat.
62:1 to 62:15 Low Your boiler's pump is set to run for a specific amount of time after the heating switches off to help the system cool down safely.
62:2 High Your boiler has detected an issue with the internal pump's operation, causing it to run for a short safety cooling period before pausing.
63:0 High Your boiler is failing to communicate properly with the equipment used to heat your hot water tank, meaning you may lose hot water.
63:1 Low Your boiler is performing a routine daily check to ensure the internal pump and components are not seized up.
63:2 to 63:14 Low Your boiler is notifying you that a specific pre-set service interval or scheduled maintenance time has elapsed and a routine check-up is now required.
63:15 High Your boiler has detected an internal electronic error that suggests the main control unit is beginning to fail, which may cause your heating and hot water to become unreliable.
65:0 High Your boiler has lost communication with the internal valve that directs heated water to either your radiators or your hot water tank, meaning your system cannot function correctly.
65:1 High Your boiler is having trouble directing water to the right place, meaning you might not have any heating or hot water until it is fixed.
65:2 High Your boiler is having trouble directing hot water between your taps and radiators due to a mechanical issue with a internal valve.
65:3 High Your boiler is struggling to switch the flow of heated water between your radiators and your hot water taps because of an internal valve malfunction.
67:0 to 67:60 High Your boiler has likely detected an internal configuration issue or a fault with the control board that manages your hot water settings.
67:40 Low Your boiler is having trouble communicating with the solar heating controls, which may prevent your hot water from reaching the desired temperature.
71:0 Low Your boiler is notifying you that your hot water circulation pump is currently active based on its programmed schedule, which may be an advisory rather than a breakdown.
71:1 Medium Your boiler is switching itself off because it is struggling to reach the correct temperature while trying to heat your hot water tank.
71:2 Medium Your boiler is having trouble heating your hot water cylinder because a sensor has detected an unusually high temperature or a fault during the heating process.
72:0 Low Your boiler is notifying you that the hot water circulation pump is currently active based on its set schedule, though it may indicate a minor communication lag with the sensor.
72:1 Medium Your boiler is switching itself off unexpectedly while trying to heat your hot water tank because a temperature sensor is detecting an unusual reading.
72:2 Medium Your boiler has detected that hot water is being heated when it shouldn't be, which is usually caused by a faulty sensor or a sticking internal valve.
73:0 Low Your boiler's hot water circulation pump is currently active based on its programmed timer settings.
73:1 to 73:6 Low Your boiler is notifying you that the hot water cylinder's circulation pump is running on a preset timed cycle to prevent legionella or keep the water warm, rather than responding to a specific heating demand.
73:7 High Your boiler communication module has a permanent fault that is preventing the system from talking to its controls correctly.
76:0 Medium Your boiler's internal communication system is failing to connect with other smart controls or external heating modules.
76:1 Low Your boiler is having difficulty communicating with its internal smart connection module, usually meaning there is a minor electronic glitch or a connection has come loose.
76:2 Medium Your boiler is having trouble communicating with its internal control modules or multiple boiler system systems, which may stop it from operating correctly.
77:1 Medium Your boiler's internal communication system has detected an issue or a duplicate identity on its data network, which can sometimes happen after a power cut or part change.
77:2 to 77:99 Low Your boiler's internal communication system has identified an addressing conflict between different control units on the network.
79:0 Medium Your boiler's internal control panel is having a communication error and is struggling to coordinate with other linked components in the system.
79:1 High Your boiler's main control unit has detected an internal communication error and is struggling to manage the various components of the heating system.
80:0 High Your boiler is experiencing a communication error between its control system and the temperature sensors, meaning it cannot accurately monitor the water temperature.
80:1 High Your boiler has detected a communication error with its internal sensors or control unit that has lasted for more than five seconds.
80:2 to 80:199 Low Your boiler is pausing temporarily to prevent it from switching on and off too frequently, which helps protect the internal components.
81:0 Low Your boiler has been manually switched to a mode where it only provides hot water and has turned the central heating off for the season.
81:1 Low Your boiler is notifying you that it has automatically switched between summer and winter mode based on the external temperature.
81:2 Low Your boiler is having trouble communicating with its external radio clock module, meaning it may not know the correct time or date for your heating schedule.
81:3 Low Your boiler is having trouble synchronizing its clock with other connected parts of your heating system.
88:0 Low Your boiler is operating normally, but the display settings have been changed or reset to show temperatures in Celsius.
88:1 Low Your boiler is simply displaying the temperature in Fahrenheit instead of Celsius due to a settings change.
90:0 to 90:199 Low Your boiler is struggling to adjust the heating temperature correctly in response to changes in the weather outside.
90:128 Low Your boiler is receiving an unusual signal from the outdoor temperature sensor, likely due to a minor communication error or a faulty sensor outside your home.
91:0 Low Your boiler is having trouble communicating with an external control accessory, meaning some remote settings or external commands might not be working as expected.
91:1 Low Your boiler has detected an external control conflict where a heating setting is trying to communicate with a part of the system that isn't configured to receive it.
91:2 Low Your boiler is experiencing a communication issue with the accessory that controls different temperature zones in your home, often caused by a temporary wiring hitch or a sensor problem.
91:3 Low Your boiler's control system is receiving conflicting instructions regarding how your heating cycles should run across your different radiators or zones.
92 Low Your solar heating system has a faulty sensor or a wiring problem that is preventing it from correctly monitoring the temperature of the roof panels.
93 Low Your boiler has detected a technical fault with a sensor in your solar heating system, which may affect its ability to heat your water using solar energy.
94 Medium Your boiler has lost communication with the temperature sensor in your hot water tank because of an electrical fault, meaning it cannot accurately monitor your solar heated water.
95:0 Low Your boiler is trying to connect to a remote control accessory that it cannot find or which has lost power.
95:1 Low Your boiler has detected an issue communicating with its remote control or internet connection module during the initial setup process.
97:0 Low Your boiler is noting a change in how it reads the outside temperature, but it is typically just an internal setting update and should not stop your heating.
97:1 Low Your boiler is receiving the outdoor weather information from another connected device on your home network rather than its own direct sensor.
97:2 Low Your boiler is having trouble communicating with the outdoor temperature sensor, which helps the system run more efficiently based on the weather.
98:1 Low Your boiler is experiencing a communication error with an external remote monitoring system, meaning the central hub cannot correctly read your heating data.
98:1 to 98:5 Medium Your boiler is confused because it doesn't know which type of heating system it is supposed to be controlling.
A0:0 Medium Your boiler has lost communication with its external thermostat or control unit, meaning it may not know when to turn your heating on or off.
A0:1 Medium Your boiler has lost communication with its remote control thermostat, meaning it cannot receive temperature instructions.
A0:2 Medium Your boiler is having trouble communicating with the wall-mounted room controller and may need a simple reset to re-establish the connection.
A2 High Your boiler has sensed that the internal pump is malfunctioning or water is not circulating correctly, which has caused the system to stop as a safety precaution.
A2:0 Medium Your boiler is currently ignoring the standard priority for hot water and is attempting to provide heating and hot water at the same time, which may result in lukewarm water or poor heating performance.
A2:1 Low Your boiler is currently focused on heating your hot water tank, so it has temporarily paused the central heating to ensure you have enough hot water.
A2:2 Medium Your boiler is likely experiencing a communication or pump error where it is struggling to switch between heating your house and heating your hot water tank.
A3:-9 to A3:15 Low Your boiler is automatically managing its pump based on the outdoor temperature to prevent your pipes from freezing.
A5 High Your boiler has detected that the water pump is likely stuck or not moving water correctly, which means the system cannot heat up safely.
A7 High Your boiler's control panel has developed a communication fault and is unable to send or receive correctly.
A8 High Your boiler's main internal computer has lost touch with the display panel, meaning the controls cannot talk to the heating unit.
A9 Medium Your boiler is having trouble 'talking' to your thermostat, which means it might not know when to turn your heating on or off.
b0 High Your boiler has detected an electrical fault with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
b1 Medium Your boiler's main control panel is having trouble talking to its own internal computer, meaning you cannot change settings or control the heating properly.
b4 High Your boiler has encountered an internal electronic communication error that is preventing it from monitoring its own performance correctly.
b5 High Your boiler has experienced an internal communication error or processor glitch that is preventing it from running properly.
b7 High Your boiler's internal computer chip has been disconnected or has developed a communication fault, meaning the system doesn't know which settings to use.
b8 High Your boiler has detected a broken connection or a fault with the sensor that monitors the temperature of the exhaust gases, causing the system to stop working for safety.
bA Medium Your boiler is having trouble communicating with the control box that manages your second heating zone, meaning that specific area may not heat up correctly.
bc Medium Your boiler has lost its connection with the remote control unit used to manage your primary heating circuit.
bd Medium Your boiler has lost connection with the remote control unit that manages your second heating zone, meaning you cannot adjust the temperature for that specific area.
be Medium Your boiler is having trouble communicating with the wall-mounted thermostat control because of a setup or configuration error.
bF High Your boiler is currently stuck in an automated filling process and cannot continue until this is resolved.
C2 Low Your boiler is having trouble 'talking' to your solar panels or an additional heating control part, which might prevent those specific systems from working correctly.
C5 High Your boiler is having trouble communicating with its internal pump, which means it cannot properly move heated water around your system.
C6 High Your boiler is having trouble communicating with the internal pump that moves hot water around your heating system.
C7 Medium Your boiler is having trouble communicating with the internal pump that moves hot water through your radiators, which may prevent your heating from working correctly.
Cd Low Your boiler has lost its connection to the remote control or internet monitoring system, so you may not be able to adjust settings via your app or external thermostat.
CE Low Your boiler is having trouble communicating with an add-on control or an external smart home accessory, which may affect its ability to run efficiently.
CF Low Your boiler is having trouble 'talking' to its internal Wi-Fi or internet connection module, which may prevent you from controlling it via apps or external thermostats.
dA Medium Your boiler has lost its connection to the indoor temperature sensor for your main heating area, meaning it cannot accurately tell how warm your rooms are.
db Medium Your boiler has lost the ability to monitor the temperature in your second heating zone because a sensor has developed an electrical fault.
dd Medium Your boiler has lost connection with the indoor temperature sensor that controls your main heating, meaning it cannot accurately tell how warm your home is.
dE Medium Your boiler has lost connection with the temperature sensor that controls your second heating zone, meaning it cannot properly regulate the temperature for that part of your home.
E4 High Your boiler has stopped working because it is not receiving the correct electrical power or an internal fuse has blown.
E5 High Your boiler has stopped working because it cannot confirm that a flame is burning safely, leading to a complete shutdown for your protection.
E6 High Your boiler has stopped working because there is not enough water flowing through the system to keep it running safely.
EL Low Your boiler is currently running an automatic air-purging program to remove air bubbles from the system and does not require a repair.
F0 High Your boiler has experienced a serious internal brain failure and the main control board likely needs to be replaced.
F1 High Your boiler has switched itself off because it has reached a dangerously high temperature, likely due to a lack of water or poor circulation.
F2 High Your boiler has shut down because it has detected it is getting too hot, which is usually caused by a lack of water or a circulation problem.
F3 High Your boiler is detecting a flame when there shouldn't be one, so it has shut down for safety purposes to prevent a malfunction.
F4 High Your boiler has failed to light the flame, which means it cannot provide any heating or hot water until the issue is resolved.
F5 High Your boiler has identified a problem with the ventilation system and has shut down as a safety precaution because it cannot confirm that exhaust fumes are being cleared correctly.
F7 High Your boiler has stopped working because it cannot correctly detect the water pressure, causing the system to shut down for safety.
F8 High Your boiler has detected a problem with the gas valve not closing correctly, so it has shut down the burner for safety.
F9 High Your boiler has stopped working because the internal fan isn't spinning fast enough to safely start the heating process.
FA High Your boiler has failed to start properly and the fan is running constantly to clear out the system, preventing the heater from firing up.
FC High Your boiler has shut down because it cannot correctly control the flow of gas needed to stay alight.
Fd High Your boiler's internal computer has crashed due to an ignition failure or electrical interference, preventing it from starting the burner.
FE High Your boiler's internal computer has encountered a critical error or is having trouble communicating with its electronic security card, causing the system to shut down for safety.
FF High Your boiler has encountered a computer processing error or the reset button is stuck, meaning the system cannot start its normal operations.
nF1 High Your boiler has detected trapped air inside it which is preventing it from starting up safely.

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
d1 Diagnostic Your boiler has stopped working because it cannot detect any water moving through the system to keep it from overheating.
d2 Diagnostic Your boiler has switched itself off because it has reached an unsafe temperature and needs to cool down before it can be used again.

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