New Shower valve

[carver]

Hi,
Firstly a basic question. I have a concealed shower mixer valve to install that has 3/4 inch female connections. What is the correct method of connecting the supplies and shower / bath filler outlets. I assumed threaded male connector with PTFE tape, but not sure. I have done many soldered and compression type joints in the past but never one of these.

Secondly, I am removing the taps from my bath in favour of a filler via the above valve. Are there blanking caps that can be bought to cover the tap holes in the bath. The bath is plastic.

Many thanks for your help.

 

[Softus]

Yes, you need a 3/4" BSP threaded male (aka "male iron") adapter.

Wind on the tape anticlockwise, for half a dozen turns, then wipe a smear of LSX round the threads and screw it in.

There are various types of adapter, including ones with a plastic push-fit socket.

 

[carver]

Softus
Thank you.

One of the shower fittings has a 1/2 inch male thread that goes through a hole in the tile. Should this be secured to the tile with the female fitting/connector on the other side, or should this first be secured with a 'threaded ring' similar to what holds a tap to a basin before connecting the female fitting. The concealed shower valve is going into a studded wall and I have complete access at the back before I board over.

Thanks

 

[Softus]

One of the shower fittings has a 1/2 inch male thread that goes through a hole in the tile.

This arrangement sounds unusual, and I'm having trouble picturing it.

Could you post a photo of the thing you're installing, and/or a hyperlink to a manufacturer's/supplier's web site?

Did you by any chance buy this from Bathstore.com?

 

[carver]

Softus,
thanks again.

I probably did not describe very well what I meant.
Please see the picture. this is the part of the shower fitting that goes through the wall (tile). What is the best method of fixing.

thanks

 

[Softus]

OK I get it now.

That does look like a 1/2" BSP thread, so your idea of a tap backnut is a very good one. Then you can just use a [fairly] standard tap connector fitting, screwed onto the threaded spigot.

However, the spigot looks a bit short, i.e. might not be long enough to reach through both the tile and the backing board. How long is it, measured from a point corresponding to the face of a tile?

Or is it a nipple that you could unscrew and replace with something longer?

Frankly, the product is weird compared to what's generally available in this country. Before you proceed, have you checked that you'll be able to get spare parts for this valve? If you can't then I'd advocate NOT fitting it.

 

[carver]

the threaded section is 20mm long from the face of the tile.
I bought the valve from Ergonomic designs. They specify that spares are available.
Following other advice I removed a small section of the backing board slightly larger than the hole in the tile, so that this fitting would fix directly to the tile. The tile is 9mm thick

Thanks

 

[Softus]

Understood.

I don't think you have any other options than clamping to the tile, although I find the thought somewhat unpalatable. I'd be tempted to find a suitable bracing plate to support the tile, or at very least a 1/2" polythene washer so that the backnut isn't graunching on the back of the tile.

When you fix it in place, put a layer of top quality silicone sealant** on the face that meets the front of the tile (you can wipe off the excess when it's tight), then from the rear inject more silicone around the spigot to fill the gap between it and the tile, then put the poly washer over that, then the nut. This will utterly stop water from creeping through the hole in the tile along the threaded spigot.

**By "top quality", I mean Dow Corning 785.

 

[carver]

Thanks for your help. I'll give it a go.
Will I get the Dow Corning silicone from any larger store likely to be open on Sunday.

 

[Softus]

I can hardly believe I'm suggesting this, but Screwfix sells it.