Shower 'Mini trap' air lock?

[daveth]

Guys

Can anyone explain this bizarre phenomena to me?

My en suite shower has a mini trap fitted.

When in use, the shower tray will start to fill up with water, but as soon as I give the trap chrome cover/hair trap a gentle tap, the tray will empty (so its draining not only the tray but coping with the shower output too - so I dont think its a partially blocked drain pipe).

It seems like an airlock is forming in the 'sump' of the mini trap.

I cant easily replace the trap for an alternative type as I cant access the connector - the floor is tiled with electric heating underneath...

Any ideas what is causing this and any solutions?

Thanks

Dave

 

[Alanc]

Did you remove the chrome cover, remove and clean hair catcher?

 

[Paulus]

This can happen on some of these traps simply because the trap isn't properly located. Try twisting it different ways to see if the flow improves.

 

[daveth]

This can happen on some of these traps simply because the trap isn't properly located. Try twisting it different ways to see if the flow improves.

Thanks for the replies.

The 'sump' of the trap locates on 4 mounts in the outlet moulding, so no scope to twist it. If the sump is incorrectly inserted (off its mounting lugs so it's sitting on the outlet base) that doesn't seem to make any difference.
The chrome top cover just drops into the sump - both are round so no again twisting that doesn't really help. I guess my gentle tap lifts the chrome cover just enough to disturb the water flow and kick start it draining.

Regarding cleaning, yes all parts are thoroughly cleaned. My paranoia has made thorough cleaning a weekly task as the last thing I need is a hair ball blocking the pipe given that I can't access the underfloor pipes.

Do you think increasing the size of the vent hole in the chrome cover might help even pressure and air flow in the sump?

 

[Phil]

Is this a B&Q shower trap? They catch hair and block up like nobodys business.

After spending ages with a wet vac and tweezers and still having is drain slow I use this now at home and a huge hair ball appears like a dead rat in the plug hole. Drains nicey now.

 

[daveth]

Hi

My trap came from Victoria Plumb, no doubt its just Chinese junk like ther B+Q stuff...

Heres what it looks like

.


My issue isnt a blocked pipe as it drains the full tray quckly when you give the chrome cover a kick. So the plunger isnt what I need.

Its really annoying especially having to explain to guests that they have to kick the drain or the shower will flood (low lipped tray)

Any ideas??

 

[SimonG]

Reduce the depth of seal, but I didnt tell you that.

 

[Paulus]

Simon said it, not me, but I agree with him.

Yes It's a Chinese clap tlap.

 

[SimonG]

I say nothing.

 

[daveth]

Seal? I don't have a seal. Or do you mean the seal between the tray and the trap outlet? Or am I missing something?

 

[daveth]

But totally agree its a Chinese clap tlap

 

[PlumbBobBob]

simon didn't mean the tube that goes into the tlap at all in any way, the bit that isn't in the middle of the picture that you didn't put up

 

[Gas]

Sounds like a common symptom of self siphonage to me, solution is to fit a waste with an AAV.

 

[daveth]

Right that makes more sense. It Gurgles as it finishes draining so that sounds like a good diagnosis. I can't access my shower outlet pipe to add an aav near the shower, but if I add one to the wash basin trap, hopefully that may help. Many thanks