Hot water coming out of tap too slow

suziqqq

Hi we have just installed a mixer tap in our kitchen. Before it had 2 separate taps for hot and cold and and the pressure was ok. Since installing the new tap the hot water only trickles out. We have taken off the isolator valve and changed it and the pressure is good but not from the tap. Any ideas whats wrong

huckster

So if you opt for cold water, how is the flow then ?

What heating system do you have for the water ?

Is there just an air lock in the pipes ?

suziqqq

cold water pressure is great, we have gas heating not a combo boiler with a tanks in the loft with dials on it and tank in airing cupboard if thats any help

huckster

Not on expert on taps Suzi, so was just asking questions so others can help later.

If you can switch the cold & hot pipes to the tap around and then try, would cold water come out with good pressure when the tap is fully on the hot. You can do this, if you have flexible plastic pipes and not rigid ones.

I hope you get what I mean. I am trying to identify whether it is a problem with the tap or the feed into it. If you switch the supply over and it still comes only slowly when the tap is on hot, then it a problem with the tap.

societys_child

Sounds like the cold water is mains pressure, but the hot water is gravity fed from the tank and under much less pressure.

Is the new mixer a quarter-turn (ceramic disc) type? If so they have fairly small holes in the discs and there's probably not enough pressure to force the water through.

emg

My mum had this problem as her hot water was gravity fed and the kitchen fitters had used the wrong sort of tap. They eventually switched it for a different sort of tap and was much much better.

jennifernil

Taps have a minimum operating pressure. Sounds like you need one that can handle low pressure. What is the spec for your tap?

suziqqq

huckster wrote: »

Not on expert on taps Suzi, so was just asking questions so others can help later.

If you can switch the cold & hot pipes to the tap around and then try, would cold water come out with good pressure when the tap is fully on the hot. You can do this, if you have flexible plastic pipes and not rigid ones.

I hope you get what I mean. I am trying to identify whether it is a problem with the tap or the feed into it. If you switch the supply over and it still comes only slowly when the tap is on hot, then it a problem with the tap.

have switched them round the cold which was the hot is fast and vice versa. Think it must be the tap spec although i don't know how to find the pressure of my hot water system to get another

DTDfanBoy

If it's a gravity fed hot water system, which it sounds like it is, you can calculate the pressure yourself.

If your header tank is 10m above your tap you'll get 1 bar pressure, 20m = 2 bar.

Assuming the tank is in the loft of a two story property you should be getting somewhere around .7 bar

southcoastrgi

wrong taps, however you will have mains cold & gravity hot so you need taps suitable for both pressures