Bath water running hot and cold

[kevin78]

Hi all,

We have a combi boiler its an REMEHA ADVANTA PLUS.

The water in the bath runs hot for a few seconds then the temp drops. in order to get it running hot again we have to turn the tap off and open it again. The same happens in the bathroom sink. The kitchen sink stays running hot but the water pressure drops and we keep having to open the tap further.

Any help would be greatly appreciated.

thanks

 

[winty85]

your combi can only heat water so fast, when you open the bath taps full the water is pulled through the boilers Heat exchanger to fast for it to be fully heated. This is usually cause by the bath being piped up with 22mm pipe instead of the 15mm like what comes out of the boiler. All you can do is not fully open your taps or fitting a isolation valve just before the bath tap and only opening it half way (again to slow the flow of water)

 

[kevin78]

have tried running the tap slower it still runs hot for a few seconds and then goes cold

 

[nogoodatfaultfinding]

New DHW heat exchanger or Diaphram if it has one

 

[bellairaphon]

diaphram or flowswitch dont know the boiler so id say one of them

Nath