ASG installed a boiler in 2014. Had a few problems and ASG staff 'talked us through' on the phone fixing them ourselves while we pay for 'unlimited call outs, repair etc... The boiler stopped working all together a year ago. An engineer came and replaced a part. ASG demanded that we have a power flush carried out (at our expense) as apparently the fault was because of debris...We had to do this or ASG said the warranty would be void. A power flush does not need to be done more than, at most, every 5 years. This year, the boiler stopped again just after the yearly service (!?). A Viessmann engineer came, replaced the same part as last year because of so-called debris. We then received an invoice for £232 for the repair! ASG indicates that the repair and call-out is not part of the warranty. ASG has now sent us a recorded delivery 'final demand'. They will not answer my emails requesting justifications for the bill. The Agreement states quite clearly that ASG is responsible for the maintenance of the boiler including all repairs and replacement parts. I managed to talk to someone on the phone who just kept on repeating, you have our final demand. I inquired about why the filter does not catch the debris and was told that the cleaning of the filter (which they fitted at time of installation) is not part of the service!! ASG are rude, customer service is non-existent. They install, take your money every month for 14 years (!) and completely wash their hands off the terms of the Agreement. They're in this game to make money on the back of people like us who are trapped in an Agreement. Terminating the Agreement would cost us £4000! It's a complete rip-off, their advertising of 'peace of mind' is a con.