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I have been warning readers for some time that British Gas service engineers are given financial incentives — and put under pressure at monthly group sales meetings — to sell extra products and services to existing HomeCare customers.
One or two of the gadgets they try to sell you — such as carbon monoxide detectors and magnetic central heating filters — do at least perform a function, albeit many readers report they have bought identical products from other suppliers for half the British Gas price.
The Hydroflow water-treatment device appears to be a new departure for BG’s marketing department, however, in that there is no truly independent scientific proof to show that electric or magnetic “limescale inhibitors” of this nature have any effect on domestic heating and plumbing systems.
There is some evidence that powerful large-scale versions used in industrial processes can have some effect. But this is in closed systems, where the same liquids are passed around a circuit again and again.
This set-up does not exist in a domestic plumbing supply, where the incoming water passes once only through the incoming mains pipe. BG’s claims that such a gadget will cut heating costs and improve the longevity of your boiler, washing machine and dishwasher are tenuous, to say the least.
As to the idea that if you refuse to buy one of these unproven gadgets, they won’t repair any faults due to limescale — well, this seems extraordinary. I am continually surprised that readers continue to give money to this firm, given the questionable sales practices that its engineers appear to follow.
In any case, living in a hard-water area does not necessarily result in a limescale problem. Many water suppliers dose the mains supply with food-grade phosphate, which keeps the calcium ions in solution and stops them being deposited as limescale. If you do have a genuine problem, then the only proven remedy is a proper ion-exchange water softener – the type that uses common salt to regenerate itself.
Daniel.