I've recently moved in to a new home. For a while the shower was draining really slow, as there was no access to the pipework (it's all tiled in), I ended up ripping the shower tray out in order to see what the problem was. The trap was badly clogged up with hair and other gunk, I cleaned it out and presumed that would sort the problem.
I put the base back in and ran water through it to test, but the problem still remains, it takes around a minute to drain a litre of water. I read that it may be because of a lack of fall on the pipe, so I raised the pipe dramatically, but it made absolutely no difference.
If I disconnect the trap, and run water through it from the tap, it's absolutely fine (it never fills, just runs straight out), similarly, if I pour water directly in to the waste pipe it drains away so quickly that I can't even see it filling up.
I'm a complete novice and have absolutely no idea what the problem could be. Any help would be greatly appreciated.