from 15mm to 22mm

[adrianfs1]

hell all
a bit confused, got a down stairs bathroom on a 1930s terrace house, combi boiler fitted therefore all water at mains pressure, the 2 tails into the bathroom are 15mm, then 22mm pipe has been connected to the 15mm to supply the bath hot and cold, with tees down to 15mm for hot and cold to basin and toilet, looks like old pipework (pre combi boiler fitted 2 years ago) i need to replace all pipe work in the bathroom, can i replace it all in 15mm 0nly, or will this have a diverse effect on the water pressure. thanks all.

 

[Plumbstar Tom]

bath should have 22mm to it

Basin and toilet ok in 15mm

 

[adrianfs1]

but why are both hot and cold into the bathroom 15mm

 

[secret squirrel]

Not sure, but I'd hazard a guess at if the hot feed from the boiler is 15mm they (fitter) may have thought why bother increasing it to 22mm same for the cold, if the hot is producing 14 ltrs per minute when on, why have the cold filling up quicker.....

 

[stevetheplumber]

hell all
a bit confused, got a down stairs bathroom on a 1930s terrace house, combi boiler fitted therefore all water at mains pressure, the 2 tails into the bathroom are 15mm, then 22mm pipe has been connected to the 15mm to supply the bath hot and cold, with tees down to 15mm for hot and cold to basin and toilet, looks like old pipework (pre combi boiler fitted 2 years ago) i need to replace all pipe work in the bathroom, can i replace it all in 15mm 0nly, or will this have a diverse effect on the water pressure. thanks all.

15 mm to every thing using 22 can cause the boiler to run on after taps closed and lead to problems some ones not bothered to replace the pipework under the bath usually due to difficultise in removing panels

 

[adrianfs1]

so do you suggest i fit all cold in 15mm and increase to 22mm for the hot bath and tee off on 15mm to basin?

 

[adrianfs1]

or should i refit all pipework in 15mm

 

[Puddle]

or should i refit all pipework in 15mm

As steve says,run in 15mm,if 15mm to bathroom,nothing gained increaseing and could cause prob,only reason you have some 22mm at present is because left over from old system

 

[adrianfs1]

thanks for that guys

 

[moony]

seen a few jobs youve asked about now adrian - are you self employed mate ?

 

[kirkgas]

if you find a mix of 15/22mm on an installation with a combi you will find that the new boiler has simply been connected to the old system with minimal alterations (ie to save some cash) a new build with a combi is all done in 15mm, rip it out and you will find a better flow (or perhaps i mean better success filling the bath)

 

[adrianfs1]

hi q-plumb and all, yes i am self employed but as property services, trying to complete nvq 2 in plumbing at mo, just want to make sure im doing the job right