Cleaning out a dated system

[CMD]

Hey!
I'm looking for advice on cleaning out a system, I want to put in something like Sentinel X800 and also a magnacleaner to fully clean it out, the house could be 70yrs old and the pipework 30yrs old, the pipework has been replaced in places and leaks cured but to fully utilise the heat from an open fire with a back boiler I want to have everything working to it's maximum, I don't know if the cleaning fluid would be too powerful without more damage or which is the best magnacleaner - which I will have to reduce from inch pipe to 3/4 to accommodate it, there seems to be no opinions on which cleaner is best on the web

Thanks

 

[exedon2]

No need to reduce pipework for filter a number of 28mm ones are available
Fernox omega would be my choice solid metal construction 25year warrant.

 

[CMD]

No need to reduce pipework for filter a number of 28mm ones are available
Fernox omega would be my choice solid metal construction 25year warrant.

Cheers dude! Ended up replacing a load of pipe as leaks kept appearing so will definitely look into it!