The f22 error on a boiler is usually caused by insufficient pressure or insufficient water being available to be pumped around the system. Before we go any further, we should point out that unless you’re Gas Safe qualified, you should never attempt any repairs to a boiler yourself, it’s actually illegal to do so, so don’t be tempted to remove the cover if you don’t know what you’re doing – get a free quote here instead. Fortunately the Vaillant boiler F22 error is rarely a fault code that costs a lot to fix.
Vaillant’s range of boilers monitor the water pressure within the system, and if it gets too low, will stop the boiler from working in order to prevent damage being caused. As the error code is shown, it will flash up on the display (it may be behind a pull-down cover) alternating between the error and the current pressure reading. There may also be other indications too, such as a flashing radiator symbol, but if your Vaillant boiler is not firing, what’s usually most helpful to an engineer in the first instance is the fault code. When the error occurs, it will typically alternate with a current pressure reading of 0.2 or 0.3 bar, which is lower than the minimum operating pressure of 0.4 bar.
What Is An F22 Fault Code?
In the image shown (yours may differ – the error code is the important bit), the red light indicates that there’s a problem with the boiler’s ability to fire up and generate a hot water supply to the taps and radiators, so has entered a shutdown state until the problem is resolved. This is both for safety and to prevent further damage. If you were to be able to run it without this cut-out, you could end up with a boiler dry fire occurring, where the boiler could start to self destruct through extreme overheating, as it’s trying to heat water that either isn’t there, or isn’t able to circulate due to the low pressure.
For clarity, the code is the same whether you’ve got a Vaillant Ecotec Pro 28 F22, an Ecotec Plus F22 fault code, or anything else. If it’s a Vaillant and that’s your error, the same problem has been detected.
To get help from a local qualified Gas Safe engineer get a free quote here.
The F22 fault code on Vaillant boilers generally occurs in conjunction with the boiler failing to provide hot water or heating. It’s often a code which flashes on the boiler display, and can often be as simple to fix as adding more water to the heating system.
Restoring Hot Water And Heating After An F.22 Error
To restore hot water and central heating to a working state from your boiler you simply need to add water, or to use a fancy term, repressurise. However, all boilers vary. It you know what you’re doing, topping up the water supply should solve your problems, but if you need help, request a quote from our network of qualified Gas Safe engineers using the form on this page. Luckily, this is usually a low cost appointment, as there are usually no further issues for the engineer to solve other than topping up the water to overcome the F22 boiler fault code. A safe operating reading should be in the 1 to 1.5 bar range. It’s also possible to experience problems at the opposite extreme, such as Vaillant Ecotec Pro 28 with pressure too high, but that’s much less common in our experience, and usually the result of someone trying to fix the boiler without the appropriate knowledge.
If you need more specifics on Vaillant F22 problems, please see the following:
Mark Ballard talks in this video about the F22 fault whaen people call telling him “my Vaillant boiler wont turn on“, and what can be done about it: