Mine's quite a simple query..connecting copper pipework to plastic,as in hot and cold copper feeds being plumbed into a plastic bodied thermostatic shower unit.
Any particular potential problems to bear in mind?
I assume that the copper and plastic pipes are both the same size .ie- 15mm .. The cleanest, quickest and easiest way is to use Speedfit, these are available as straight couplings, elbow, tees and reducers. They are made of white plastic suitable for hot and cold supply on both copper and plastic. These simply push onto the pipes..job done, they are also de-mountable and re-usable, The only drawback to Speedfit is that are a little bulky. If you are tight for space you can also use brass or chrome compression fittings but be sure that the plastic pipe is 100% clean and scratch free otherwise they could leak especially under mains pressure.