shall i change the pipes from 22mm to 15mm

[goofy gorilla]

hi guys

i have a run of 5m of hot and cold pipes from my combi boiler.....along the roof space in the kitchen to the bathroom roof space, they are then reduced down to 15mm and into my thermostatic bar shower...i find that the water is not as hot as it should be....will reducing the pipes to 15mm make any difference...also the pipes are covered with pipe lagging....?..ta

 

[ScottishGasMan]

No, reducing the pipes to 15 wont sort that problem, if anything it would be worse.

are the hot taps every where giving plnty of hot water? if so, you may have a fault on the mixer shower. if not then i think its more the combi that needs to be looked at to make sure its giving out the energy to the hot water its supposed to be giving.