Do you have a Vaillant boiler that is showing a fault code on its display? Is this fault code something that you are unfamiliar with or do not know how to solve? Boiler Boys London have created this blog post to help you with some of the most common Vaillant boiler fault codes that may help you fix your boiler, or identify a problem that we can fix for you.
It is incredibly important to understand the fault code and the exact problem that it refers to when your boiler is not functioning smoothly. This is because any persistent problem with a boiler can lead to it becoming permanently damaged, which could be very expensive to solve. That is why it is incredibly important to get your boiler serviced at least once a year. If you live in London, near areas including Hanwell, West Ealing, Acton, Ealing, Chiswick or Kensington, then Boiler Boys can provide you with our professional boiler servicing service.
Here are some of the most common Vaillant boiler faults that can help you with troubleshooting the problems that you may be facing.
Vaillant F22 Boiler Fault
One of the most common Vaillant boiler problems is the F22 fault code. This fault refers to a lack of pressure or water in the system. This problem occurs mostly in the EcoTEC Plus and EcoTEC Pro models. As most modern boilers are equipped with sensors that constantly measure the pressure of the water in the system, in Vaillant's boilers, there may be a red light showing on the display screen which confirms that the boiler is not operating correctly.
Can I fix an F22 Fault?
Some people think that the F22 fault can be easily fixed by using the filling loop to top up the pressure on your boiler, however, not only does this not fix the problem but it can dilute the chemicals that are protecting the system.
A leak in the system is the most common issue for the F22 fault, however, you require a professional Gas Safe registered engineer to identify this for you. That is why it is essential for you to call a heating engineer when you see the F22 error code because if your boiler continues to operate while this code is showing, then your boiler could be functioning with a deficit of water in the system, which could lead to the complete damage of your boiler. You should switch your boiler off and wait for a professional inspection.
Vaillant F27 & F28 Boiler Faults
These codes either refer to the boiler's flame not working correctly; either the PCB is not working or the gas valve is not working correctly (F27) or the boiler has a frozen condensate pipe meaning that the condensate waste cannot run into the drain and is trapped in the boiler, meaning that the boiler cannot function (F28).
Can I fix an F27 or F28 Fault?
You may have to simply wait for the condensate to defrost in order to fix this fault. If the pipe runs outside, then you could pour hot water over the pipe to defrost it, or place a bucket under the boiler and disconnect the plastic waste pipe on the far right of the boiler, before draining the condensate into the bucket. If this does not work, then you will have to call a professionally qualified Gas engineer to inspect the boiler and its internal components.
Vaillant F29 Boiler Fault
If the code F29 flashes up on your boiler then this indicates that the boiler flame has been extinguished. As this problem is to do with gas, then it is always sensible to call a Gas Safe registered engineer to come and help you fix the problem. However, this could be a problem that you could fix yourself if there is a problem with the gas supply to your boiler. For example, the meter may have run out, there are gas repairs taking place on your road, or your gas supplier has cut off the gas.
How to fix an F29 Boiler Fault?
If it turns out that there is no problem with the gas supply to your boiler, then your professional gas engineer will test the gas valve operation and adjustment settings, check the condition of the ignition leads and check the condition and operation of the ignition unit are all running smoothly.
Vaillant F75 Boiler Fault
This fault is the most common Vaillant boiler fault. It is particularly common in the EcoTEC Plus range of Vaillant boilers. If the F75 code is flashing in your display, the fault is most likely to do with the boiler’s sensor not registering the fact that the pump has started running, thereby failing to register a change in pressure. This commonly happens in some of Vaillant's older models that are equipped with a Wilo pump instead of a newer, improved Grundfos pump. A build-up of sludge can block the pressure sensors in older Vaillant boilers.
Can I fix an F75 Boiler Fault?
You can do a quick manual check of the pump on your Vaillant boiler by simply turning on the heating or hot water. If you hear a low humming sound when the boiler starts working, this is the sound of the pump circulating the water through the pipework, which means both your pump and boiler are working just fine. However, if there is no sound after you have turned on the boiler, then this indicates that your pump is faulty. If your pump is no longer working, then you will need to call a gas engineer to come and replace the pump or sensor of your boiler.
