How to Balance a system

I have a bungalow with 8 rads set out on a \\\'Y\\\'.
I would like to know how to balance the system as I have hot and cold rads.I have no idea how to do this and have tried many times.The only other info I can give you is the seems to be a a pair of 22mm pipe that run around the false roof.The rads in each room seem to be fed from each of these pipes.I would think one if flow the other return.
PLease help
thanx in advance
FLY

ps all the rads have thermostatic valves on the end other than the bathroom

See reference section

I did look there first to no avail..

Could you please post the link
many thanx
PAUL

Try this link

http://www.diydata.com/projects/centralheating/balancing/balancing.htm

I found it P&H Forum at the top under sticky for ref..then follow nose

hope it helps