Mixer tap error, is this fix ok?

[david1805]

Hi all,

Ok, hands up I have messed up installing a shower mixer tap. I have replaced a 'telephone' style bath/shower tap with separate taps and a wall mounted shower mixer and naively thought that teeing off the taps wouldn't be much different to how it was with the old mixer tap. So I now realise that I have mains cold and gravity hot.
Does this have any chance of working whatsoever?
If not, I can fairly easily route a pipe from the cold water tank down the soil pipe boxing under the bath and into the pipe that feeds the mixer - would this be ok? Next question - what size should this pipe be? The hot is 22mm, apart from the 15mm feed to the mixer, should the cold feed from the tank also be 22mm? At what point should I reduce it to 15mm?
Many thanks in advance for your help
David.

 

[seco services]

Does this have any chance of working whatsoever?

not really

If not, I can fairly easily route a pipe from the cold water tank down the soil pipe boxing under the bath and into the pipe that feeds the mixer - would this be ok?

not really

Next question - what size should this pipe be? The hot is 22mm, apart from the 15mm feed to the mixer, should the cold feed from the tank also be 22mm? At what point should I reduce it to 15mm?
Many thanks in advance for your help
David.

if you run your shower off the hot supply to the bath and a cold supply from the loft it will still be a hopeless shower

you'll more likely need it pumped if you want a descent shower not a water can effect.