03-02-2012, 05:39 PM
(This post was last modified: 03-02-2012, 06:24 PM by Radio Fixer.)
Very interesting Mark. I knew nothing about the Weather Compensation technique. On sealed systems a thing that happens to some is that it wont hold pressure after the new installation. This happened to my neighbour with his 70's house and was put down to the downstairs pipes being in the concrete floor screed. Back then the pipes were not covered and apparently the lime etc causes micro leaks, not enough to allow water to escape, but they wont hold pressure. So he had to have all new pipe work, done as a drop system from the upstairs floor. Certainly something to be taken into account if having such a system... ups the cost considerably.
On power flushing I didnt do this when I upgraded the system last year. I fitted all new rads and flushed the pipe work with suitable couplings and a hose, plenty of mains pressure here. At this time I replaced the HW cylinder and put in new primary pipework to it. This is gravity feed and I know its old fashioned but its so beautifully simple and I dont have a motorised valve anywhere (they fail eventually). I do have of course a wireless tank (boiler) thermo and a room one (pump). The cylinder is vertically above the boiler and it works very well now. I was amazed how coked up the old pipe work was, just a small hole down the centre of it. No wonder gravity wouldnt circulate thru it.
I wonder if the header tank and drawing in oxygen is a bit of sales pitch? Since the upgrade with a good refill of anti-corrosion mix the system is completely quite, never seems to need bleeding and everthing works fantastci. Did put the best (expensive!) rad valves on all the upstairs ones and one giant rad in the hall. These as far as I can tell just work... in the summer screw them closed and now set as required.
cheers Gary
On power flushing I didnt do this when I upgraded the system last year. I fitted all new rads and flushed the pipe work with suitable couplings and a hose, plenty of mains pressure here. At this time I replaced the HW cylinder and put in new primary pipework to it. This is gravity feed and I know its old fashioned but its so beautifully simple and I dont have a motorised valve anywhere (they fail eventually). I do have of course a wireless tank (boiler) thermo and a room one (pump). The cylinder is vertically above the boiler and it works very well now. I was amazed how coked up the old pipe work was, just a small hole down the centre of it. No wonder gravity wouldnt circulate thru it.
I wonder if the header tank and drawing in oxygen is a bit of sales pitch? Since the upgrade with a good refill of anti-corrosion mix the system is completely quite, never seems to need bleeding and everthing works fantastci. Did put the best (expensive!) rad valves on all the upstairs ones and one giant rad in the hall. These as far as I can tell just work... in the summer screw them closed and now set as required.
cheers Gary
