fitting new cloakroom basin

[Carolyn]

We need to replace a cloakroom basin and at the same time intend to fit isolation valves to the pipes. We intend to use push-fit or speed-fit ones but I keep seeing them being referred to as either service valves or isolation valves. Can anyone tell me the difference (if there is any)?

[EliteHeat]

One end of a service valve fits onto the tap itself, so is a tap connector, the other end fits onto the service pipe.

An isolation valve fits to a plain pipe at both ends, usually via compression or speed fit.

[Paul Barker]

yes that's what they are called at the merchants but actually any valve which is there for preservation of water when working on the appliance including the gate valve which feeds the dhw cylinder is a service valve.

When I say service valve I am referring to all but the stop cock.