Trevi therm shower fitting question

[Chri5]

On the above mixer the inlet feeds are 3/4", so I've used 22mm pipe and that goes to a compresion / olive fitting that then screws to the inlets.

I'm about to close up the wall and tile the shower area, this will be several weeks before I can feed the water supply in via a negative pressure shower pump.

Maybe I'm having a 'blonde' moment, but could someone confirm that There's no need for washers to be fitted between the 3/4" fitting and the 22mm copper feeds and that the olives on the fitting provide a full seal.

Thanks

 

[Gasguru]

I assume you have standard 22mm compression fittings on the shower valve.

The olives in theory will provide the seal. However it is not uncommon to find evidence of slight leaks several months down the line if you do not use a jointing compound in addition.

Smear an approved compound (eg Fernox water hawk) around the olive and especially the thread. This will significantly reduce friction when tightening. Be careful not to allow any sealant into the valve since it may cause blockage and damage.

 

[Jasonb]

You are more likely to get a leak where the 22x3/4 MI fitting screws into the mixer body, these threads should have PTFE etc on them.

You should at least flush all the pipework through before connecting the mixer and head otherwise you risk muck getting into them and its a By-law. If you cant get water to it do dry a pressure test.

Jason

Jason

 

[Jasonb]

Ps This is why trevi give you the plastic fitting for flushing the mixer BEFORE any water gets to the mixing valve.

Jason

 

[Chri5]

Thanks guys

I've used PTFE around the screw threads of the fitting and I'll rig up the plumbing to allow mains water for flush out and as a half way house regarding leak test.

As always I indebited to you for the advice, any electrical questions just ask and I'll try to help