The Consumer Rights Act 2015 says goods must be as described, fit for purpose and of satisfactory quality. During the expected lifespan of your product your legal rights entitle you to the following:
up to 30 days: if your goods are faulty, then you can get an immediate refund.
up to six months: if your goods can’t be repaired or replaced, then you’re entitled to a full refund, in most cases.
up to six years: if your goods do not last a reasonable length of time (bearing in mind their nature) you may be entitled to some money back.