Thanks for the tip,but does it alter your meter reading much?Isuppose you have to run the system to get it through to you pipes or else you will end up with frozen pipes?GOOD TIP 4 next year cus were for a bad winter sometime just so h/s can tighten up on the use of w/f/p in winter after a few people have slipped on the ice,I get around this by carrying a bag of building sand with me,dont charge for it at the moment but will do next year.