Slow flow from 10mm pipe in wash basin

[Murmansk69]

I've just fitted a new wash basin by connecting 10mm plastic pipes using Hep 2 0 pipe and fittings.

I'm getting a slow rate of flow from the hot tap - about half as fast as from the bidet tap which come off the same pipe a few inches away and I think it may be due to one of two reasons and I'd be interested in anyone's thoughts on which is most likely to be the cause:

1. The pipe support sleeves I used were plastic and clearly intended for a pipe of a slightly smaller internal diameter - I wrapped a bit of PTFE tape round them to make them snug fit. The correct ones would have been slimmer and metal I think.

1. I have one of those in-line tap devices in the pipe before it goes down to 10mm - a compression fitting operated by a screwdriver so you can isolate the tap - I've just noticed I fitted it with the arrow on the outside going against the direction of flow.

[The Medway Handyman]

That could well be the problem.

[Doctor Drivel]

or a high pressure tap on a low pressure system.