heating system

[johnant]

can anyone give me a link to go to where i can see a good diagram on how my central heating works seperately from hot water thanks
also i need to know how to drain my heating system?
i tried this but it was draining smaller tank in loft and that was just filling up i want to drain all radiators
thanks

[jocky]

What you want to do is tie the ball valve up to a piece of wood on you small tank (feed and expansion tank) to stop it opening when draining down. The larger tank in your loft will be supplying you hot water cylinder.
This link may help
http://www.gasman.fsbusiness.co.uk/system_basi cs.htm

[winny]

I not know much but mr W a plumber and you must use some chemical stuff when you fill back up to stop black sludge forming. People empty rads and weaken the sludge reducer stuff and the gunk builds up blocking boiler and then that causes trouble. So if you empty rads you will loose all sludge reducer and must replace it.
maybe shouldnt have told you that just did some plumber out of a power flush job.