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If your Viessmann boiler has stopped working or is showing you some error message, you can easily sort the matter by doing a simple restart. Just like restarting a phone or computer, resetting your boiler can help clear minor faults and get it working again.
Boilers can lock out as a safety measure when they detect an issue, such as low pressure or a temporary glitch. Before calling an engineer, it’s worth trying a reset yourself. It’s quick and easy and could save you time and money. So, let’s see how to reset Viessmann boiler!
Understanding Viessmann Boilers
Viessmann boilers not only save energy and heat and circulate hot water but also ensure efficiency and reliability. To find out how this is possible, let’s explore their main components, their types, and their safety features.
How They Work
A Viessmann boiler burns the fuel for heat. This heat warms the water in the heat exchanger, which then circulates through your radiators around your house.
A setting panel is also available where you can make setting adjustments, track the operation, and also reset the system when required. Newer models also incorporate temperature and pressure-monitoring sensors for optimum operation.
Types of Viessmann Boilers
Viessmann offers three primary types of boilers:
- Combi boilers – Heat and hot water are provided when needed. Ideal for small houses where space is not available.
- System boilers – Utilize an independent hot water cylinder. Ideal for bigger houses where hot water is needed from multiple taps simultaneously.
- Regular boilers – Otherwise referred to as traditional boilers. They need the tank and the presence of the cylinder, thus being suitable for traditional heat systems.
Safety Features
Viessmann boilers also contain multiple safety features:
- Overpressure valves – Relief the overpressure to prevent damage.
- Overheat protection – This shuts the boiler when the temperature is excessively high.
- Flame failure device – Prevents the gas from being supplied when the fire goes out, preventing leaks.
- Carbon monoxide alarm – Warn you about potential gas leaks.
Regular maintenance is the best practice for the operation of these safety features. Refer to your manual or obtain the advice of a professional if you need it.
Why Do You Need to Restart Your Boiler?
Modern boilers will turn off by themselves when something is not right. This is called the boiler lockout, where the operation is not performed under hazardous conditions. In some instances, you can resolve temporary faults by resetting your boiler and restoring the operation to normal.
A Viessmann can lockout for many different reasons, some including:
- Low or high water pressure – If the pressure is under 1.0 bar or over 3.0 bar, the boiler will turn off for safety.
- Ignition failure – If the gas supply, blocked burner, or faulty ignition components fail to light the boiler, the boiler will enter the lockout mode.
- Blocked heat exchanger – Scales from limescale buildup or debris from the system can block the passage of the water and cause the boiler to overheat.
- Faulty sensors – If temperature or pressure sensors detect faulty readings, the boiler will switch off to prevent even greater damage.
Most Viessmann boilers will also flash the error code onto the control panel, showing you the nature of the problem. If you can’t recognize the code, you can find advice by consulting your manual.
Understanding Fault Codes and Error Messages
Viessmann boilers also come with a diagnostic system. If something is not functioning correctly, they will provide you with error codes for you to find the cause. These are some error codes:
- Fault Code 10 – Loss of fire (most likely due to gas supply faults).
- Fault Code 20 – Fan problem (may affect airflow).
- Fault Code 30 – Defective burner (would not allow the heat to work).
These codes make faults easily discoverable by engineers. In the unfortunate situation where you find yourself encountering one, you can use your owner’s manual or internet fault finder. If you can’t figure them out, you’d do best leaving the job for the professionals.
How to Reset a Viessmann Boiler After a Fault Code
When a Viessmann boiler senses something is not right, it will flash the fault code and turn off the boiler to avoid causing even greater damage. In some instances, the problem can be solved by the simple act of resetting the boiler.
How Do You Reset a Viessmann Boiler?
Before resetting, check the error code and make sure you don’t have some serious issues like gas leaks or overheating. If all is fine, follow the following:
Step 1: Locating the Reset Button
The reset switch for the Viessmann boiler is generally placed on the control panel. This may say ‘Reset’ or will display the round arrow icon.
If you’re not sure where the Viessmann boiler reset button location is, you can check your manual for your specific model.
Step 2: Turn Off the Boiler
Before resetting, turn the boiler off using the main switch. Let the system cool for a few minutes and reset internally.
Step 3: Hit the Reset Button
Press and hold the Viessmann boiler’s reset button for about 5 seconds. In some models, you will need to hold the button for a longer period or press several buttons together; the manual will explain the specifics.
For newer models like the Vitodens 050 or the Vitodens 100, the process may possibly be slightly different.
Step 4: Turn the Boiler Back On
Once you’ve pressed the reset button for the specified amount of time, turn the boiler back on using the main switch. The boiler will start the process of restarting, which can take some minutes.
Step 5: Monitor the Boiler Display
After restarting, check the display panel of the boiler for the error code. If the reset has taken hold, the boiler will start operating normally.
If the error code remains or is now different, you may possibly have something deeper going on that will require professional servicing.
Step 6: Monitor the Boiler
Over the next few days, observe your boiler’s work. If you find your heat is erratic, your water pressure is decreased, or your boiler is shut down frequently, you’d best call for the expertise of a gas-safe engineer for inspection.
How to Reset Viessmann Combi Boiler
Resetting a Viessmann combi boiler is the identical process for all models. Because combi boilers provide hot water immediately, make sure all the taps are turned off before the reset.
If your Viessmann boiler is continually locking out, repeated resets will not work. In this scenario, you require professional help to avoid causing further damage or increased energy consumption.
How to Reset a Viessmann 050 Boiler
Resetting a Viessmann 050 is simple, provided you follow the appropriate procedures so as not to cause further faults. This is how you can safely reset it.
Step 1: Double Check These
Before resetting, make sure your boiler is ready:
- System Pressure – Read the gauge. This will need to be around 1.0 and 1.5 bar. If you discover the gauge is low, you will need to repressurise.
- Gas Supply – Leave the gas supply for the boiler turned on for the boiler to function properly.
- Power Supply – Check your fuse box and make sure the boiler’s circuit breaker is switched on.
Step 2: Restart the Boiler
- Press and hold the ‘OK’ and ‘Mode’ simultaneously for 2 seconds.
- Release the buttons and check the display screen.
- If an error code (i.e. F2) appears, refer to the manual or call the heating engineer.
Step 3: Is It Working?
- Wait a few minutes and verify if the radiators start warming up and hot water is being supplied.
- If the boiler doesn’t restart or shows another error, call a Gas Safe registered engineer.
Safety Tips
- Never open the casing of the boiler or tamper with internal parts.
- If you can smell gas, call the National Gas Emergency Helpline.
- If your Viessmann 050 boiler is continuously shutting down, a professional inspection is likely called for.
How to Reset Viessmann Boiler F2
The F2 fault code means your boiler’s burner has been locked out. This stops it from heating water or providing central heating.
Why Does the Viessmann Boiler F2 Fault Happen?
This issue is typically the result of a circulation problem rather than the burner. These are the usual causes:
- Blockages – Mud, sludge, or rust clog the pipeline, stopping the passage of the water.
- Pump Airlocks – Trapped pockets of air restrict the flow of the water. If your pressure is compromised or you hear humming noises, the culprit may be an airlock.
- Ventilation Issues – Inadequate ventilation or blocked flues can affect the combustion.
- Pump Problems – If the pump is not installed correctly or is not calibrated for the right speed, the boiler will not operate.
- Cold Weather – In the event the condensate line is frozen, the boiler will turn off.
- General Wear and Tear – Debris over the years or worn parts can lead to loss of flame or overheating of the equipment, causing an F2 error.
How to Fix the F2 Fault
If your boiler is showing the F2 error, follow these simple resolutions prior to phoning for professional advice:
- Reset the Boiler – Turn the switch located under the lid of the boiler and let the boiler resume operation.
- Check the Wiring – If the reset fails, check the wiring connections (do this only if you know your stuff).
- Repressurise the System – Low pressure will cause an F2 fault. If need be, refer to the manual for the boiler for pressurising the system.
- Thaw Frozen Pipes – If the pipes freeze during very cold weather, thaw them by gently warming the pipes using hot (not boiling) water and wrapping them around for insulation against future freezing.
How to Reset a Viessmann Vitodens 100 Boiler
Resetting your Viessmann Vitodens 100 is very simple. This is how you can do it:
- Check the Display – If your boiler has shut down, the display will likely display an error code. Record this.
- Press the Reset Button – Locate the reset button on the control panel. Press and hold for 5 seconds.
- Wait for the Restart of the Boiler – The screen will flash or will require some seconds for the reboot.
- Check if It’s Working – Is the hot water and heat back to normal?
If the boiler fails to start up again or is continuously switching off, something is likely the matter. Call for the help of a Gas Safe registered engineer.
Viessmann Boiler CL Error Reset
A CL error on your Viessmann boiler signals the mode is standby mode or the need for the mode to be reset. To address this, follow the following:
- Press the Reset Button – Hold the press for some seconds until the display is restored.
- Check the Pressure – If the pressure is below 1.0 bar, you will need to repressurise the system.
- Ensure Gas Supply Is Turned On – Ensure the gas is turned on for the boiler.
- Restart the Boiler – Try again after all the checks.
If the CL error is persistent, you can check the manual for the boiler or obtain professional advice.
How to Reset a Boiler When the Gas Runs Out
If your Viessmann gas boiler fails, the cause may be the gas being empty. Try the following steps:
- Check if the Gas is Available – Try using your gas stove or fire and verify if gas is flowing through.
- Turn the Gas Supply Back On – If the gas was off, ensure it’s now open.
- Press the Reset Button – Hold for 3-5 seconds until the boiler is resumed.
- Wait for the Boilers to Restart – If gas is flowing through correctly, the boilers will start up again.
- Check for Fault Codes – If the boiler is not functioning, check for the error message and adhere to the instructions given by the manual for the boiler.
If your boiler will not reset, the gas line could potentially have an airlock. In this instance, you will require the help of a gas-safe engineer.
What to Do After Resetting
Once your boiler has been reset:
- Monitor it – Ensure that it remains turned on and functions correctly.
- Look for error codes – If you find them, refer to the boiler manual.
- Test heating and hot water – All is working fine.
If problems keep recurring, the best option is to call a professional heating engineer for them to inspect and sort the matter out.
Why Do I Have to Keep Resetting My Boiler?
If you continually reset your boiler, chances are you have some underlying fault not being repaired. Resettling will only remove the error for the short term, and the issue will come back.
Common causes include:
- Low water pressure – Your system will require repumping.
- Blocked heat exchanger – Debris or limescale can cause overheating.
- Broken pump – If the circulation is not normal, the boiler will shut off.
- Gas or electrical faults – Faulty supply can cause repeated shutdowns.
Troubleshooting Common Viessmann Boiler Reset Problems
Resetting a Viessmann boiler does not necessarily always work the very first time. These are some faults and their solutions.
Boiler Lockouts
A lockout is when your boiler has detected something is not right and has shut off for safety.
Causes:
- Burner blockages
- Low water pressure
- Sensor or ignition faults
What to do:
- Check the display for the error code.
- Refer to your manual for the directions.
- Press and hold the reset for 10 seconds.
If the boiler won’t restart, contact Viessmann customer support or a heating engineer.
Low Water Pressure
Your boiler will not heat properly unless the pressure is high enough.
How to check
Look at the gauge for the pressure – ideally, this will range from 1 to 1.5 bar.
How to fix
- Use the loop for refilling the tank.
- Bleed your radiators to remove the entrapped air.
- If the pressure is declining, you can expect you will require professional work to be done.
Heat Exchanger Malfunctions
A blocked heat exchanger can also make your boiler less efficient and unable to heat your home.
Preventative steps
- Get a yearly service to clean and inspect it.
- Consider a softener for your water if you live where the water is hard.
Avoiding Common Issues
- Keep an eye on the levels of pressure and error codes.
- Learn how to bleed radiators to expel the trapped air.
- Ensure there’s good ventilation around the boiler to prevent overheat.
Advanced Issues and When to Call a Professional
Some problems require professional skills. Call a Gas Safe registered engineer if:
- Your boiler keeps shutting down despite multiple resets.
- There are repeated error codes or strange noises.
- You notice leaking water or the odor of strong gas.
A professional will also be able to troubleshoot complex faults, keeping your boiler running safely and efficiently.
The Bottom Line
If your Viessmann boiler is being regularly reset, something is causing the problem. These can range from low pressure through gas supply faults, faulty pumps, and blockages.
To reset your boiler is simple: find the reset button, press and hold for some seconds. But where the problem is recurring, you need the skills of a gas-safe engineer.
Keeping your boiler regularly maintained, keeping the levels topped up, and servicing your boiler each year can all prevent the need for resets. If your boiler is old, maybe the best solution is replacement.
Frequently Asked Questions
Find the reset switch on the control panel. Press the switch for about 5 seconds until the boiler resets.
The reset switch is generally located on the front panel of the boiler, next to the display screen. Refer to your manual if you can’t locate the switch.
Locate the reset switch, hold it for 5 seconds, and allow the boiler to restart operation. If this doesn’t work, check for error codes and possible faults within the system.
Possible reasons for this error may include low water pressure, gas supply, power, or faulty system. Consult the error code that your boiler displays for additional information.
Yes, you can also reset it by using the reset button. However, if the problem remains, you can contact a Gas Safe registered engineer for fear of causing further damage.
