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Vaillant F75 Boiler Fault – Guide and Advice

F75 Boiler Fault - Vaillant error

One of the common water leaks that we deal with is central heating boiler leaks and, it can require some technical leak detection exploration, which thankfully we are experts at. Something that can indicate you have a water leak is a loss of boiler pressure – for example, an F75 boiler fault error on a Vaillant Boiler (not ‘Valliant Boiler’ as some call it!), such as the Vaillant Ecotec Plus combi boiler.

This was actually number three on our article on the signs of a water leak.

Boiler Error Fault Codes
Various Boiler Error Fault Codes

Finding water leaks in the (often) hidden pipework of a central heating system is not something that is easy to do yourself, and plumbers are not necessarily equipped for. In fact, we get jobs sent to us from plumbers or heating engineers who believe a leak exists but are unable to find it in a home or business.

Please note – different models of boiler and different manufacturers will have different error codes so consult with your manufacturer or manual to find out what your code means. That said, this guide provides information relevant to various. If in doubt, feel free to contact us for help.

Good examples of where F75 Boiler Fault leaks may occur (which we have useful guides for) include the following:

In this article, we will look at F75 boiler fault codes specifically (although this also applies to similar codes on other boilers too) and what might cause the error, which will appear on the display panel, which will look something like this…

Boiler Pressure Gauge - F75 Fault Code
Boiler Pressure Gauge – F75 Fault Code / Error Display

For more on this, see our useful article about having a combi boiler leaking and, on an associated note, our thoughts on central heating leak sealer or our guide to Central Heating Leak Detection.

What is an F75 Boiler Fault Code?

To get the answer straight from the horses mouth, on the Vaillant website they have a Vaillant Fault Codes page, and for F75 codes they say “Fault: Pump/ water shortage: Water pressure sensor and/or pump defective, air in the heating installation, insufficient water in the product”

So let’s look at those things one by one:

  • A faulty or broken pressure sensor
  • A defective boiler pump
  • Air in the system
  • Insufficient water

So clearly, of the four, the first two are possible faults with the boiler and two could be faults in other parts of the system, linked to boiler pressure / a potential water leak in the central heating. On the subject of pressure, you may be interested in our article about how a pressure relief valve works.

So how do you know which is the cause? Well if you have ruled out a fault with your boiler, for example by having a Gas Safe engineer check it out following an F75 boiler fault, or if you have other signs of a water leak (including pressure loss) then it’s possible a leak in the pipes is causing the issue.

A water leak can cause boilers to lose pressure and add air to the system, so if you are losing pressure fast and having to top up your boiler and you have an F75 boiler fault code, get in touch with us and we will discuss this with you. Remember, we provide free consultations and quotes if needed.

F75 Boiler Error
F75 Boiler Error Vaillant

Finding an F75 Boiler Fault Leak

As leak detection experts, we have both the people, processes and leak detection equipment to help maximise the chances of finding any water leaks in your properties, and not just for F75 boiler fault leaks – we can find all sorts of leaks in your property.

We have written a full article on our step-by-step approach to trace and access leak detection which is well worth a read to understand the process from start to finish. That said, here are some of the methods we will use to find your water leak, during our leak detection process:

Speaking of tools, we have a new one we have developed which is useful to this whole topic. You can see how much water you might be losing with our Boiler Pressure Leak Calculator

Remember, if you have Trace and Access cover, the cost of finding and fixing the water leak could be paid for by your insurance company. We can work with you and them to manage that process, for all types of leak, not just F75 Boiler Fault water leaks.

Trace and Access Services
Trace and Access Services

Unlike some other water leak detection companies, we are water damage restoration experts which means that apart from actually finding the leak, we will also help to evaluate and assess the damage caused to your property by the water leak. We can also help dry and restore your property after. logo logo

How do I fix Vaillant F75 error?

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A Vaillant F75 boiler fault error is often associated with a drop in water pressure, water loss from your boiler or central heating system, which can include a water leak. Depending on what is causing that pressure loss, that will determine the best fix. That could be a problem with the boiler itself, or as we said a leak. If it is a leak then in order to fix the F75 boiler fault error, you will need to find and fix the leak, otherwise pressure will continue to drop.

Can I fix boiler pressure myself?

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It is not advisable to attempt to fix boiler pressure yourself (unless you are a qualified and accredited boiler engineer). Plus, you are unlikely to be able to understand what is causing the boiler pressure problem. For example, it could be a problem with the boiler or a water leak in the central heating pipes, which will most likely require leak detection specialist help to find it.