DIY Doctor

Main navigation

Help With Newbie Combi Boiler Question With Poor Cold Water Pressure

Postby Weaveworld » Wed Dec 20, 2017 4:53 pm

New to the combi boiler thing so a few questions if I may? I know I have no cold water tank, not cylinder - makes sense! but why is the cold water pressure in the house so poor? any why does the cold water usage affect the hot water pressure?

Eg. If I am running a bath on pure hot water its pretty slow - if I add cold water too via the mixer tap, the water flow doesn't increase at all, just gets cooler? I would have thought the volume of water coming through would be from mains AND boiler, and therefore increase?

Similarly, if I flush the loo before jumping in the shower, the shower pressure dips dramatically until the cistern is full... the temperature remains the same but the flow is reduced...

I do have one of these limescale remover things plumbed in near the mains, so I wonder whether that is restricting overall pressure? the outside tap, which doesn't come through that, seems fine?

Just FYI it takes about 14 seconds to draw a litre of water, cold or hot - which seems slow to me but I have no real benchmark!

Any advice or info gratefully received!
Rank: Labourer
Progress to next rank:
Posts: 1
Joined: Wed Dec 20, 2017 4:48 pm


Simply Build It

  • DIY How to Project Guides
  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!

  • Related Topics