We found Pure Gas after trying two other local firms. The first said the boiler was beyond economical repair after looking at it for 2 minutes and the next one said it probably needed several expensive components replacing and quoted £400 for the job. I thought I'd get a third opinion and called Pure Gas who came that same afternoon. They quickly identified the problem and picked up a part locally from Plumb Center and fitted it on the same day. My Vaillant combi boiler is now working perfectly, it's only 5 years old and they even showed me the receipt for the part they bought for my boiler so I know they charged me fairly. Their bill was just under £100 including the part and I couldn't be happier with their service. I would certainly recommend!