Fit the machine as in the instructions
Turn it on with all rads fully open
Flush for 10 mins with water only,this way if something is about to go it wont waste costly chemicals,or melt the carpet
Put the chemical in ,run for 10 mins to let it get to all the rads
Shut all the rads off except one
Flush this radiator for at least 10 minutes,altering the flow direction occasionally ,then open another and shut the first one
Keep doing this until they have all been done
Flush out to drain from each radiator individually,this makes it easier to see when each run is clear as the pipe runs clearer coming to the machine
If possible isolate the primary circut to the cylinder for most of the flushing or it will waste valuable flow from the heating circuit.Primary and coil can be flushed same as a rad
If you can,run the boiler on very low .(with central heating pump saftely disconnected)
This also helps the chemicals work
This way you can feel if all of the radiator has cleared or not
If you get cold areas in the rad then bang it with a soft mallet or your hand until it becomes hot(this helps dislodge stuck on stuff)
A magnaclean unit makes ,in my opinion,a big difference
We have done 100 or so flushes using genuine Kamco chemicals and machine and only a couple were probably not worth doing
Most of the flushes have made a huge difference to the systems
Dont rush it,if it takes less than most of the day you are not doing it properly (average house)
I trained at Kamco all be it after we had done 30+ flushes
Good luck