Vaillant ecotec F.27 fault

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I can repair your Vaillant ecotec F.27 problem with one visit. I specialise in Vaillant combi boiler repairs. Please give me a call on 07515058714 to arrange a visit by a local Gas Safe registered Vaillant expert.

Should you happen to have a Vaillant ecoTEC boiler you may find yourself presented with the F.27 fault code at some point. Generally this fault allows you to reset the boiler and it continues work for a period but eventually it will stop working altogether leaving you with no heating and no hot water(Combi models). As a homeowner you cannot fix this problem yourself. This essentially gives you time to call someone suitable to fix the problem before it stops working altogether.

The F27 fault is most common on the first generation of Vaillant ecoTEC’s manufactured between 2005 and 2012. You can tell if you have one of these models by the round controls knobs on the front of the boiler, as shown in the images below. The front digital display looks slightly different between Plus and Pro models but this problem affects both models the same.

So what is the F27 fault? If you look at the manufacturers instructions it actually says “Incorrect sensing of flame”, and under the cause section says “flame sensor defective”. Unfortunately its not that straight forward. To any “engineer” reading this, the flame sensor is usually at the very bottom of the list of possible causes of this problem. If the flame sensor(electrode) is clean and it can conduct electricity then it doesn’t need to be replaced!

Unfortunately a lot of the time the printed circuit board is the cause of the problem. As a homeowner there is nothing that you can do(legally) to fix this problem. You need to call a heating industry professional who is Gas Safe registered to inspect the appliance, determine the cause of the problem and offer a solution. As with most faults on these boilers there should be no need for any guesswork.

All of the components I have mentioned (flame sensor, printed circuit board) can be tested in various ways to determine what needs replacing to fix the problem. No guesswork should be necessary for any “engineer” to offer a resolution to the F27 fault. Replacing parts on boilers based on guesswork is almost always an expensive endeavour for someone.

As an end user your only option is to call a heating industry professional who is competent and Gas Safe registered to fix the problem.

I carry around 80% of the spares available for the first generation Vaillant ecoTEC boilers manufactured between 2005 and 2012. I can usually get one up and running within one visit.

It is important to note that this is NOT intended to help other engineers and it is most definitely NOT intended as a DIY self help guide for homeowners trying to fix their own boilers.

If you are an engineer seeking information on how to fix this problem and this has been helpful in some way then thats great. However this page is for information purposes only and cannot be relied upon by someone attempting to carry out any repair – regardless of their qualifications. Read my disclaimer before attempting to use any information on this website.

vaillant f27 fault code

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locationI am based in Wath-upon Dearne, Rotherham, South Yorkshire. I cover the whole of Rotherham and most of South Yorkshire, including Sheffield, Barnsley and Doncaster.

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I cover the whole area of Rotherham including central Rotherham, Brinsworth, Catcliffe, Canklow, Masbrough, Treeton, Whiston, Greasbrough, Kimberworth, Thorpe Hesley, Rawmarsh, Wentworth, Bolton-on-Dearne, Goldthorpe, Thurnscoe, Wath-on-Dearne, Mexborough, Swinton, Kilnhurst, Hooton Roberts, Ravenfield, Thrybergh, Bramley, Hellaby, Maltby, Thurcroft, Wickersley and Braithwell.
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