The Vaillant Boiler F54 fault code, and all Vaillant boiler fault codes, show on the screen on the front of the boiler when there is a problem and your boiler locks out.
Vaillant uses them to show you what might be wrong with the boiler. Having fault codes on the screen is a great way to help diagnose your boiler problems.
I have been carrying out boiler repairs for over 10 years and having fault codes on the screen when I arrive is very welcome. Not all boilers use fault codes, so having them is a huge bonus.
What Does F54 Mean on a Vaillant Boiler?
The Vaillant boiler F54 fault code means insufficient gas supply. Similar to the Vaillant boiler F28 fault code (not getting any gas), the F54 fault code means not getting enough gas.
This means the boiler will not work as the gas valve is not supplied with enough gas to heat the water in the boiler.
How to Fix F54 Fault on a Vaillant Boiler
To fix the F54 fault code on your Vaillant boiler, the first thing I would check is the ECV (emergency control valve) at the gas meter is fully open. The ECV is fully open when the handle is in line with the gas pipe.
If the handle is across, or not fully in line with the gas pipe, then the gas may be getting restricted by the ECV, causing the boiler to lock out and show the Vaillant F54 fault code.
Other Causes of an F54 Fault Code
After checking the ECV at the gas meter, here are some other possibilities that could be restricting the gas supply and causing the F54 fault code –
- Undersized gas pipe supply from the gas meter to the boiler – Needs to be upgraded.
- Blocked or dented gas pipe – Gas pipe might have built up with debris inside or been accidentally damaged. The gas pipe will need to be cleaned out or replaced.
- A partially closed isolating gas valve on the gas pipe – Full length of the gas supply will need to be checked for gas valves and make sure they’re fully open.
- Not getting enough gas to the property – The gas will need to be tested with a manometer to see if the property is getting enough gas. If it’s not, then the gas supplier is responsible to make sure it is.
- Faulty gas valve – The gas valve might need to be replaced.
How to Reset a Vaillant Boiler
The first thing I would do on a Vaillant boiler that is not working, no matter what fault code is showing, is to check the pressure and reset the boiler.
Knowing how to reset a Vaillant boiler is the simplest way to get your boiler working again, as it might have just locked out.
To reset a Vaillant boiler, you must find the reset button. This is usually a flame with a line through it. You have to press the button to reset the boiler. Sometimes you have to hold it down for 3 seconds, but on some Vaillant boilers, it just needs to be pressed.
Vaillant Boiler F54 Fault Code FAQs (Frequently Asked Questions)
How do You Clear the Fault Code on a Vaillant Boiler?
To clear the fault code on a Vaillant boiler, you must reset the boiler. If the fault code appears after resetting the boiler, you will need to find and repair the problem causing your Vaillant boiler to lock out and show a fault code.
Why is My Vaillant Boiler Not Turning On?
If your Vaillant boiler is not turning on at all, nothing on the display, then you probably have an electric supply issue.
You should check the fused spur switch that should be next to the boiler. Make sure it is switched on and the 3 amp fuse is good. It could also be that the fuse at the main board (consumer unit) has tripped, so you can there also.