Shower Mixer / Rail outlet

[paul1]

Hi there need some DIY advice from some of you experts.


I'm just about to fit a new shower mixer and outlet, which will be partly recessed in a brick wall behind Marmox type waterproof cement boards, installed by dot and and dab and wall fixings. The mixer valve has 3/4 BSP, so I purchased some 3/4 BSP to 15mm compression valves from SF. I'm fine with the copper pipework to connect all up, but just not sure about the connection. I've searched various forums and the consensus seems to be loads of PTFE or Loctite thread to seal is all that is required. The reason I ask is would nobody looking at the pictures use any type of washer in between them? There clearly is room for one between the two flat edges? See pictures.


2nd question is about the shower outlet. Same type of question really. I purchased an end feed female 1/2 BSP to solder onto the outlet copper I will run from the mixer valve. I'm also aware I need to place this carefully to sit in the right position in respect to the finished tile level. From looking at the distance (side on) at the fitting fully screwed home in the female BSP, it needs to be about 5mm behind the tile level to sit flush. So the question is does this again seal up just using PTFE / loctite or could I use a rubber washer as there are two flat surfaces that butt up against each other perfectly inside. See pictures.


Thanks


Paul
Shower Valve/Mixer
https://www.btcloud.bt.com/?shareObject=93632e9d-5215-9a1b-2a72-e07378f07016


Outlet
https://www.btcloud.bt.com/?shareObject=7cc25c09-74c3-e5ef-4faa-b21f0372fc79
https://www.btcloud.bt.com/?shareObject=df3156a7-22e2-a152-faa7-9aefc0762169

 

[paul1]

One more question if anyone has any suggestions. The docs for my Mixer say I need isolation valves for servicing and annual check of the TMV by shutting off he cold.
As the pipework will all be hidden behind the wall and the floor will be tiled I don't know where to put these, all all pipework is hidden. The only thing I can think of is a small access panel, on the kitchen ceiling below. Anyone know of some really small ones, maybe downlighting size? I don't fancy one of those large Manrose things the sell in SF.

 

[ShaunCorbs]

locktight 577 on the threads and you can put a 1/2 fibre washer in first if it has a flat face on the bottom

Pegler Ball Valve Blue 15mm | Ball Valves | NoLinkingToThis

Pegler Ball Valve Red 15mm | Ball Valves | NoLinkingToThis

 

[paul1]

Hi Shaun thanks for he advice, have ordered some 577 today.

 

[ShaunCorbs]

Hi Shaun thanks for he advice, have ordered some 577 today.

Good do your soldering first eg on the male iron and put a bead on the threads all the way round on the first couple of threads then screw the fitting on and leave to dry about 24 hours will do

 

[Radioman]

One more question if anyone has any suggestions. The docs for my Mixer say I need isolation valves for servicing and annual check of the TMV by shutting off he cold.
As the pipework will all be hidden behind the wall and the floor will be tiled I don't know where to put these, all all pipework is hidden. The only thing I can think of is a small access panel, on the kitchen ceiling below. Anyone know of some really small ones, maybe downlighting size? I don't fancy one of those large Manrose things the sell in SF.

Your shower not and cold supplies should be on individual supplies. Eg cold from own outlet on storage tank hot from either a flange or first draw on the cylinder. This is where you put your full flow isolators. This is supposing that you are not on a Combi boiler or unvented system. If the latter you shouldn't mess with it, get a G3 plumber in

 

[paul1]

Hi Radioman, I have a Combi. I am replacing an existing thermostatic shower mixer and re-tiling, it's not a new shower, the new two way valve ads the extra outlet to the slide rail, the Mrs has demanded showering without getting hair wet from the overhead. The existing hot and cold are already there plumbed in. The reason I'm asking is the existing set up does not have the isolation on the H and C that feed it under the floor then up the wall,that my instructions for the new valve mentions.

 

[PlumbBobBob]

with a combi you don't really need additional isolation to the pipes, but good practice, just turn the cold mains off and it will isolate all the water in the house hot and cold

 

[Radioman]

Hi Radioman, I have a Combi. I am replacing an existing thermostatic shower mixer and re-tiling, it's not a new shower, the new two way valve ads the extra outlet to the slide rail, the Mrs has demanded showering without getting hair wet from the overhead. The existing hot and cold are already there plumbed in. The reason I'm asking is the existing set up does not have the isolation on the H and C that feed it under the floor then up the wall,that my instructions for the new valve mentions.

Just make sure that the new shower valve is ported specifically for a Combi boiler, not a multiuse or gravity.