Pipe / valve sizes

My central heating is push fit plastic stuff.
22mm for the main circuit and 10mm for each radiator branch.

I want a more stylish radiator / valve but the majority come in 15mm.

I don't want to replace the pipe runs.

Can I just use 15mm valve on the radiator and a 15-10mm reducer behind the wall thereby just replacing the immediate piping/valve?

 

Great, much simpler and cheaper.
It's easy if you know what you are looking for!