Viessmann F7 Fault

February 15, 2023

A Viessmann F7 fault occurs when the burner is locked out, which may happen while the burner is on or off and should recover when power is interrupted. In some cases, a manual reset will be required. Read on to learn more!


What Does Viessmann F7 Fault Mean To My Boiler?

If you get a Viessmann F7 fault, the burner is locked out. This is because the boiler is not getting water and therefore cannot produce steam. To fix this fault, you must check whether the pump is running or not. If it isn't, then check whether the pump has tripped. If it hasn't tripped, your boiler's power supply should be checked by an electrician to ensure that there are no high-voltage surges. Once the power supply has been checked, you can check whether your pump is working by removing the front grille and seeing if it is rotating. If it isn't rotating, you will need to replace your pump. If your pump rotates, but there is still no water being supplied to your boiler, you will need to call a plumber to fix this fault.


What Is The Main Cause Of Viessmann F7 Fault?

The most common cause of this fault is a short circuit between the two ribbon cable segments. If you carefully look at the connector where the ribbon cable plugs into, you should be able to see if there is any damage to it. If there is, then it’s likely that this is causing you a problem.

To resolve this issue, you will need to replace the ribbon cable.

This guide will take you through how to replace the ribbon cable on your Viessmann F7 boiler.

Before starting any work on your boiler, we always advise that you disconnect the power at the main supply and ensure that there is no residual water in your system.

The next step would be to remove the ribbon cable and check if there are any visibly damaged areas on it. If there are, you may need to replace it with a new one or at least resell it properly with some professional equipment or tools.

You can also try removing the ribbon cable from both ends of its connectors and then reinserting them back into place, making sure that no other wires or cables are blocking your way. This might help fix your problem if there was some kind of disconnection between the two ends of the ribbon cable itself.


Benefits Of Contacting A Professional To Correct Your Viessmann F7 Fault

The F7 Fault is a very common problem with these boilers. A fault usually causes it in the gas valve or thermocouple, but it can also be caused by other things such as a faulty thermostat or a faulty pressure switch.

When you have this problem, you will often notice that your boiler will not ignite at all or that it will only ignite for a few seconds before cutting out again. If this happens to you, you should contact a professional to correct your Viessmann F7 Fault. Here are some of the reasons why you should hire a professional:


They know exactly what they're doing

Professional technicians are trained and experienced in handling all heating system problems. They know how to use the right tools and equipment, which means the job will be completed efficiently and adequately. They also know how to fix any issues that may occur during their work, so you can rest assured that everything will be fine once they leave.

They have the correct tools and equipment needed

Professional technicians use high-quality tools and equipment that allow them to perform their jobs well. This ensures that they get the job done quickly and efficiently while providing your home with better service delivery.

You'll save money

If you're trying to fix a problem yourself, it may not be as effective or efficient as having a professional come round and sort it out. This means that if you decide to hire someone else in the future, your boiler will already be working properly and, therefore, less likely to break down again.

They'll be able to tell you if there could be any other problems with your boiler

They will be able to tell you if there are any other problems with your boiler. For example, if your water pressure is too low or high. They'll also be able to tell if there's an airlock in your system - which could result in an explosion!

You will save time

If you try to fix your Viessmann F7 Fault yourself, there's no guarantee that you will get it right the first time. You may need to call out an engineer if something goes wrong with your boiler or heating system again in the future. If you call in a professional straight away, they can diagnose and repair the fault quickly, which means that you won't waste any more time trying to fix it yourself!

You will get better results

If you try to fix your Viessmann F7 Fault yourself, there's no guarantee that you will get it the right first time. You may need to call out an engineer if something goes wrong with your boiler or heating system again in the future. If you call in a professional straight away, they can diagnose and repair the fault giving a better result which means you won't have to experience the fault frequently.



Contacting a professional means that you will potentially save yourself a lot of time. Additionally, you should get good results faster than if you tried this on your own. Some people like to try and fix issues on their own, but when dealing with complex systems like your boiler, it is sometimes best to let the professionals deal with the problem.

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Please remember, we’re heating experts so if you need your boiler repaired, a new heating installation or if you’re struggling with anything we’ve discussed here feel free to get in touch with us now so we can see how our solutions might help you.

Thank you for reading.



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