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If your boiler displays a fault code, it isn’t always something to worry about. It could be a simple fix that you can do yourself or it may require the knowledge of an expert.
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We strongly advise that you do not touch your heating appliance yourself and always seek advice from an installer as soon as possible. They will have the expert knowledge to diagnose the issue and hopefully be able to clear the fault code. It’s important that if you smell gas, you need to vacate your property immediately and call the National Gas Emergency Service number on 0800 111 999.
NEARBY INSTALLERS
Installers from our Vaillant Advance loyalty scheme know your heating system from inside out. We help you find the best installer near you.
Find an installer
VAILLANT SPECIALISTS
Quick help: Our Vaillant expertise is just a phone call away. So, if you have any error codes, contact our customer service directly to arrange an appointment with one of our specially trained technicians. Profit from our know-how – since who knows it better than the brand who built it.
Get in contact
Even better than eliminating error messages? Avoiding errors. This is possible thanks to our 364 days live monitoring of connectivity ready heating appliances. It’s part of our service plan and, ensures optimum performance and safety. And if a fault does occur, you will receive the fastest possible appointment.
Of course, you can simply book your service appointment when you need it. But a missed fault code can cause equipment breakdowns in the long run and result in unnecessary costs. With our Service plans, you can rely on our timely reminders.
Regular checks and remote monitoring for efficient heating and energy reduction directly lower your energy costs. Also resulting in a longer lifespan of your boiler.
The Vaillant service technician adjusts your heating system perfectly to your needs from remote and during every service. By that, you can always enjoy the ideal room and water temperature.
We automatically remind you of upcoming heating maintenance to guarantee you the best care for your heating. And if the worst should happen and your heating system breaks down during the winter, you can rely on priority service and a technician who knows your heating for many years.
You can tailor your service package to your individual needs: You have the choice between cost-efficient basic contracts or comfort and all-in packages for no additional labour, travel and spare parts costs to control costs.
myVAILLANT offers a range of useful functions to control and monitor your heating system – conveniently via your smartphone. For example, you can detect faults in your heating system at an early stage and prevent them from occurring in the first place.
There are a number of benefits for using myVAILLANT, especially when it comes to boiler fault codes:
Early error code recognition on your smartphone enables quick diagnosis and problem solving.
Detect potential problems early with the Health Check feature.
Always keep an eye on your heating performance and optimise energy efficiency.
Benefit from the user-friendly and intuitive app even without technical knowledge.
Contact your local installer to install a myVAILLANT connect pack**.
**Only works with post 2006 eBUS equipped appliances. Please check the compatibility with your installer.
Have your myVAILLANT connect installed and connect your Vaillant heating system to your WiFi.
Download myVAILLANT app, register and activate your smart home subscription.
The official boiler fault code list for Vaillant systems is only available from us. You find it at thetop of this page. We update it continuously so that it is always up to date. If you don't find your error code here, contact our customer service under 0344 736 0049.
With our service contracts you can prevent many faults in your heating system. Because our experts keep an eye on your device, make sure the settings are correct and contact you proactively when maintenance is due. In this way, your heating system runs efficiently and safely in the long term. In addition, you can use the myVAILLANT app to conveniently view and optimise all the functions and data of your heating system on your smartphone at any time.
The code F20 means: "The safety cut-out (SCO) interrupts the gas valve control. The gas valve was closed because the temperature of the flow or return temperature sensor has exceeded the maximum limit." To solve the issue please check our recommendation in the official overview list at the top of this page.
The code F22 means: "No/insufficient water in the product or the water pressure is too low." To solve the issue please check our recommendation in the official overview list at the top of this page.
The code F25 means: "The flue gas temperature is too high." To solve the issue please check our recommendation in the official overview list at the top of this page.
The code F28 means: "The flame signal was not detected during the ignition phase." To solve the issue please check our recommendation in theofficial overview list at the top of this page.
The code F29 means: "The ignition following a flame loss during operation was unsuccessful." To solve the issue please check our recommendation in the official overview list at the top of this page.
The code F75 means: "The pressure change is too low when the heating pump is started up." To solve the issue please check our recommendation in the official overview list at the top of this page.
