Developed in the late 1990s the Potterton range of boilers were made specifically for the new build housing market and many builders chose to use the Potterton range due to their value for money and particularly compact size.
A neat little boiler the Suprima 50 had few faults when new and always worked efficiently. A particular fault often proved to occur after a number of years of use as the printed circuit boards would dry out and the joints of solder within the board would get so dry that electrical faults would occur often causing the boiler to lock out intermittently. Very often the problem would go away for a while then return.
Other than the dry circuit board these boilers were and some still are going strong. I have one still going strong after 14 years of continuous use. The only thing which has needed to be repaired is the circuit board and leads. This was an easy DIY repair and was done for the cost of the reconditioned board which was around £50. Much much cheaper than a new or replacement boiler.
The first way to diagnose a fault with your Potterton Suprima is via the panel behind the hinged cover to the right hand side of your Potterton boiler. The first time you get a Lock out on your boiler, meaning that the boiler shuts down resulting in you having no instant hot water and cold central heating radiators.
If you check behind the cover of your boiler there is a small panel at the top with a red light and a green one. A steady green light and your boiler is working normally. Flashing red light means that it is locked out and will need to be reignited by pressing the reset button. This usually fires the boiler back up and should then run normally. When your circuit board is suspect you find that you get lock outs intermittently at first then it happens more often and eventually will not fire the boiler.
Changing the circuit board for a reconditioned unit will be the only thing that will rectify the problem unless you are an expert in electronics and can resolder the minute cracks of solder within the board.
Circuit boards are readily available on the internet and are normally sold on an exchange basis as they are no longer manufactured by Potterton and are obsolete in that sense. For more boiler replacement information in the UK see quoteaboiler.co.uk site
article source: http://hubpages.com/living/How-To-Repair-Your-Potterton-Suprema-Boiler