This was a repair I did on a Vaillant ecoTEC Plus 831 combi boiler recently for a customer of mine in Rotherham S66. It started off as an intermittent issue which only seemed to affect the central heating, where it would not come on at times.
Covid Update November
I am doing my best to keep people warm this Autumn/Winter, hence I am still working currently and will continue to do so beyond Thursday the 5th of November 2020. I am doing my best to follow government guidelines which includes the wearing of a face mask etc.
When I got there the boiler had failed to working completely. There was a relay clicking on the printed circuit board and it would flick between showing the pressure at 0 bar, there temp at 0 degrees and then the temperature at 24 degrees.
If you look up the Con error code in the installation manual it says the following;
“no communication to mainboard – connection error display mainboard”
Vaillant ecoTEC plus 831 F.64 fault – printed circuit board failure
This was printed circuit board failure for sure. After having turned it off several times it then flashed up with the F.64 fault code and the “Con” fault message which is much less common. The F.64 by itself is usually indicative of a circuit board issue.
The “Con” fault means that there is a communication(connection) problem between the main printed circuit board and the user display printed circuit board. The Con fault by itself could potentially be an issue with the user display printed circuit board but on this occasion it was definitely an issue with the main board.
I was able to get this boiler up and running with one visit with the parts I carry. I usually around 3 printed circuit boards for the first generation Vaillant ECOTEC and at least 1 printed circuit board for the second generation models manufactured from 2012 onwards.
Looking for a Vaillant ecotec printed circuit board(pcb)?
I have added several links for anyone(heating industry professionals) looking to purchase a Vaillant ecotec printed circuit board. The first two links are for printed circuit boards for the 2005 – 2012 Vaillant ecotecpro/plus models, and for the Vaillant ecotec pro/plus models manufactured from 2012 onwards.
The parts cover the combi boiler and system boiler versions but not the heat only versions which is a different part number. The pre 2012 ecotec combi and system boilers can be identified as having a pressure gauge in the bottom right hand corner, where the post 2012 models do not have a physical pressure gauge only a digital read out.
The heat only part number is to fit the ecotec Plus 415, 418, 428 and 428. I advise you double check you have the right part number before ordering any parts.
Buy Vaillant ecotec Pro/Plus printed circuit board (pre 2012) on Amazon.co.uk
Buy Vaillant ecotec Pro/Plus printed circuit board (post 2012) on Amazon.co.uk
Buy Vaillant ecotec Plus 415, 418 etc heat only printed circuit board on Amazon.co.uk
Areas where I can repair your Vaillant ecotec plus 831 combi boiler
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.