Hot and Cold Water Reversed Throughout House - But Fine After Shower (TRY #2)

[wallymik]

Hi,

Ever since we moved into and refurbished our new house, the plumbing has been strange to say the least.

The faucets in the kitchen and in every bathroom do this weird thing where the water comes out a little warm when we set the tap to maximum cold, and a little cool when we set the tap to maximum hot. The even weirder part is, after one of us has taken a shower, the problem goes away (hot is steaming hot, cold is frigid). But if it's been a few hours since the last shower this remains a problem. All our faucets are the single-control type where you turn one way for hot and the other for cool, but are different makes (Grohe, Hansgrohe for the bathrooms and Gessi for the kitchen).

Our builder is simply mystified and says we have to live with it. I can't accept that - there must be a solution.

Has anyone seen this before? Any advice would be helpful.

Thanks,
WM

(NB I did post this earlier but was told to re-post as a member)

 

[oz-plumber]

Sounds like a problem with the shower mixer.

Try running a cold tap near the shower and see if the mixer tap get warm.

If so, the mixer cartridge has a problem.

Ask the builder to get the plumber back.

 

[Chalked]

Your shower mixer needs non return valves fitting.
Forget your builder, get a plumber.

 

[SimonG]

Faucet? Not UK?

 

[PhoenixServices]

As chalked and oz said its the shower mixing when off.

 

[Worcester]

Our builder is simply mystified and says we have to live with it.

if you are in the UK, your builder HAS to fix it. - Consumer Rights Act 2015

 

[justlead1]

There are numerous reasons for the issue. Long dead legs on the hot supply, cold supply running parallel with C/H pipes, non return valves, demand from of parts of system, etc Its time consuming to identify cause and costly.