Vaillant ecotec F61-F62 fault code(s)

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This page contains information regarding the Vaillant F.61 and F.62 fault codes including the potential reasons this may cause your boiler to break, details about my Vaillant boiler repair service and what you may be able to do about this fault if you experience it.

Vaillant F.61 and F.62 fault codes explained

If your Vaillant ecotec pro or plus combi boiler or system boiler is displaying the F61 or F62 error or fault code(will show as F.61 or F.62 on your boiler), your boiler is broken and likely needs a repair. If you have either of these fault codes you can first try resetting your boiler using the reset button which is a flame with a cross through it.

My general advice to homeowners regardless of their fault code is to try resetting your boiler first to see what it does. In relation to these fault codes your boiler will likely do one of two things after a reset – it may fire up and continue to work for so long, or it will attempt to fire up and go back to the fault code you started with.

If your boiler decides to work after a reset then it buys you some time to find someone suitable to repair it. The F61 or F62 fault code hardly ever sorts itself out and your boiler is likely to fail completely at some point and will need to be repaired.

The good news is that the F61, F62 problem can usually be repaired economically and you probably do not need a new boiler!

Vaillant F.61 and F.62 fault codes explained in detail

If you are looking for more information regarding these faults I have provided this below.

If you look at the Vaillant ecotec installation manual under the troubleshooting section it says the following regarding the two fault codes;

Regarding the F.61 fault it says “Gas–valve control defective” with the likely cause being “Short circuit/earth (ground) leak in cable harness to gas valves, gas valve assembly defective (earth/ground leak from coils), electronic control system defective”.

Regarding the F.62 fault it says “Gas valve shutoff delay” with the likely cause being “Gas valve leaking, electronics defective”.

The descriptions in the installation manual varies slightly between models and different generations of the Vaillant Ecotec. To the average homeowner this information is not of much use, and even if any of it made any sense I would highly recommend against attempting to repair this fault or any fault on your boiler.

When it comes to repairing these faults a lot of the time the fault is with the printed circuit board(pcb), which is essentially the brains of your boiler. However the fault could also lie with the gas valve or even the wiring harness within the boiler. On top of that there could be other issues with your boiler which are causing problems or could cause your boiler to break down at a later date.

Faulty Vaillant Ecotec printed circuit board
Faulty Vaillant Ecotec printed circuit board

For these reasons I highly recommend trying to find someone in your area familiar with your Vaillant boilers for a service and repair. Whenever I am called to fix this problem(or any problem) I always check over the rest of the boiler for unrelated pre existing problems that are looking to cause problems later on.

Your boiler has a lot of different components, many of which are moving parts or sensitive electrical components. On Vaillant boilers this includes components like the pump(s), pressure sensors, diverter valves, thermistors(temperature sensors) and even gaskets.

I reset my boiler and its working will it continue to work?

After a reset your boiler may continue to work for some time, maybe hours or even days but in my experience the F.61 or F.62 fault code will cause your boiler to stop working completely at some point in the near future.

My boiler works after a reset is it safe to use?

In my experience Vaillant Ecotec boilers are safe to use after a reset due to the F.61 or F.62 fault code. HOWEVER, lets assume that the issue is with the printed circuit board which controls the boiler.

The printed circuit board controls every single function and component on your boiler, which includes the pump, gas valve, fan etc.

If your printed circuit board is failing, although unlikely it is entirely possible for your boiler to become unsafe due to the fact that this component controls the entire combustion process.

So if your boiler is still working even intermittently I would suggest you get it looked at by a professional as soon as possible. With most faults especially the F.61 and F.62, your boiler will cease to function at some point leaving you without hot water or heating.

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Areas where I can repair your Vaillant ecotec F.61, F.62 fault

areas that are covered

I am located in Elsecar, Barnsley, South Yorkshire. I cover a large part of South Yorkshire including most of Sheffield, Rotherham and Barnsley. I also cover a small part of Doncaster.


I cover most of Sheffield including central Sheffield, Chapeltown, Ecclesfield, Grenoside, High Green, Oughtibridge, Thurgoland, Wortley, Aston, Aughton, Swallownest, Todwick, Hillsborough and Stannington.


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.


I cover most of Barnsley including central Barnsley, Birdwell, Stairfoot, Worsborough, Kendray, Ardsley, Athersley, Monk Bretton, Lundwood, Royston, Brierley, Cudworth, Cortonwood, Great Houghton, Shafton, South Hiendley, Brampton, Darfield, Wombwell, Hemingfield, Elsecar, Hoyland, Jump, Barugh Green, Cawthorne, Darton, Dodworth, Gawber, Mapplewell, Pogmoor, Staincross, Wilthorpe, Worsbrough, Thurnscoe and Tankersley.


I cover a small part of Doncaster including central Adwick, Conisborough, Edlington, Warmsworth and Mexborough.