Water not draining fast enough in new shower

[joddle]

Help please - We have just spent a fair bit of money having the bathroom in a small flat modernised. One of the principle things we changed was having the old metal bath removed and a walk-in shower installed instead - and it does look much nicer.

However, when we came to test the shower the water simply wouldl not exit fast enough and the shower tray soon fills up and overflows. We looked at the trap supplied with the shower and it has a small cup inside into which fits the water outlet. Thinking this may be the problem we took out the trap to see if the water will exit better and it does to a degree - but not quite fast enough to stop the water level gradually rising in the shower tray.

One thing we noticed is that as the water level drops is that air seems to bubble back through the drain into the shower which I would not have expected. Is there a logical reason for this? It seems to me that this may be casuing the water not to drain away fast enough! but I am no expert so am guessing. The wash basin and the toilet empty perfectly.

Another issue which may be affecting things is that the shower outlet is some four or so inches lower than the one that was in the bath. We have used the same pipe connection for the shower as was used in the bath - so could that be influencing the problem!

Another issue is that being a flat built in the 80s, we cannot see exactly where the outlets actually go to all we have is the places they enter the flat though the concrete floor!

The builder who installed the system seems at a loss as to the cause of the problem - so I am getting another plumber to have a look but would welcome any comments people here may have as well.

As this flat is normally rented for holidays we are desparate to find a solution as we are unable to take tenants at the moment.

 

[Charnwood]

Another issue which may be affecting things is that the shower outlet is some four or so inches lower than the one that was in the bath. We have used the same pipe connection for the shower as was used in the bath - so could that be influencing the problem!

Highly likely.
If the current trap is 4 or more inches below the position of the bath trap, water must be going uphill, unless alterations were made to the original pipework. Were there? Is there still an adequate fall in the pipework?

The 'small cup' helps form the water trap. Do not remove it.

The builder installed it - badly, by the sounds of it. He should foot the cost of any remedial work required.

 

[joddle]

I have the feeling you are right - the floor would only allow the pipe to be almost horozontal I think so maybe within the floor there is a slight rise somewhere - but of course we cannot see that - and to be fair nor could the builder have seen that. Perhaps the bath being that bit higher created enough fall to ensure a reasonable flow!

 

[Nige F]

Not all Sussex builders are as good as us old Sussex Plumbers - it may be possible to re route it .Though in a flat it might be a b`gger . or you might just have to raise the shower tray

 

[joddle]

Alas the flat is in Spain - Valencia to be precise - we can't re route the pipe as it dissapears into a void between our flat and the one underneath - and anyway it would mean breaking out the shower and undoing aload of the work already completed. For the short term we are going to restrict the flow of the shower a little - it really is pretty powerfull at the moment - much more than we have at home and that just may be enough to get us by until we decide whether to lift the shower tray up onto a small plinth or not. At least that option would be relatively easy!!!

 

[Nige F]

Spanish Builders . Your idea of estricting the volume from the shower is a good option - you might find a shower head that has a finer spray - thus giving a satisfactory wetting , and using less water

 

[joddle]

Well now I feel a lot better!!!

Having secured the services of a well reputed plumber to inspect the installation, I decided to poke my flexible drain cable down the pipe to see what direction it went and for how far. The was a little resistance but nothing too drastic and I assumed all was well.

When the plumber arrived he ran the shower at full bore - and guess what - the drain ran perfectly - I felt such an idiot. The plumber advised this was common after construction work and that we still need to get a long drain brush and give the tube a good clean and so now am off the the DIY shop to get a long verison of a bottle brush. Meanwhile many thanks to all who have helped. Its good to know there are so many experts around.