Ask a tradesperson


Mixer taps not mixing hot and cold

I have just moved into a new place and have a mixer tap over the bath which also runs the shower.
When I put the hot tap on it takes a good few minutes for the hot water to come through, then I put the cold on and it seems to take forever for the cold to start coming through and make the water a decent temperature! I seem to spend ages adjusting the taps to get it so it's not scolding hot or freezing cold. I had a mixer tap shower in my last place and never had this issue ? Its supplied by a combi boiler which has been recently serviced

4 Answers from MyBuilder Plumbers

Best Answer

I’d say the mixer is at fault. If the combo it’s a bit far, it would take a while for the hot water to come to the tap, but there’s no reason to take ages to put it on cold again.


Answered 30th Dec 2019

A combi boiler should supply hot water fairly quickly with a short lag time for the water to circulate. Cold water should be from the mains and should be instant.
You need to check that the hot water is connected to the hot side of the tap and the isolating valves is open fully. You should also check that the cold water is from the mains supply and not the tank on the loft....also check the isolater on the boiler hot water outlet to see if it is fully open.


Answered 12th Jan 2020

This points to one of two issues. The type of mixer tap if it is a standard non thermostatic shower it could be difficult to get the right hot to cold mix.
Although it could still be a faulty cartridge. The answer to this is to replace existing shower with a thermostatic shower which will balance hot and cold water for comfort


Answered 31st Dec 2019

Combination boiler has mains water feed. When you turn on the cold the pressure is reducing to the boiler this will increase temperature to the hot for a short time making hard to balance try turning on the cold water first


Answered 6th Jan 2020

Post your job to find high quality tradespeople and get free quotes

Can’t find an answer? Ask a new question

Question Categories