Why three, not one
Anyone can call themselves reliable. An accreditation means someone independent has checked, and each of ours checks something different. Gas Safe Register is about whether we are qualified and legally allowed to work on gas. Which? looked at how we run the business and treat customers. Worcester Bosch recognises our training and our record of fitting its boilers.
None of them covers everything on its own. Gas Safe does not get involved in prices or contracts, and Which? does not inspect workmanship. Together they cover the safety of the work, the way you are treated and the guarantee behind the boiler, which are the three things most people want to know before letting a heating engineer into their home.