Take a look at what Which! has to say... http://www.which.co.uk/consumer-righ...t/your-rights/
I see this
What you need to do to prove your claim
If your claim under the Sale of Goods Act ends up in court, you may have to prove that the fault was present when you bought the item and not, for example, something that was the result of normal wear and tear.
Six months...and counting
If your claim is about a problem that arises within six months of buying the product, it's up to the retailer to prove that the goods were of satisfactory quality, fit for purpose, or 'as described' when it sold them e.g. by showing that the problem was caused by an external factor such as accidental damage. Beyond six months, it's up to you to prove that the problem was there when you received the goods even if it has taken until now to come to light.
So you may need to prove that the fault was not down to ordinary wear and tear or damage you caused, and that the product (or a component) should have lasted longer than it did. To do this you may need an expert's report, for example from an engineer or mechanic.
Also take a look at what the CAB have to say http://www.adviceguide.org.uk/englan...eplacement.htm
(I include CAB as my sister has worked for them for many, many years; prior to that, she worked for Which!)