Hot water pressure issue

30 Dec 2014
Reaction score
United Kingdom
hi all

Having an issue with our hot water.

In our system we have a hot water cylinder and cold water tank. We are in a flat so the pressure isn't great from the tanks so there is a pump which increases the pressure on the hot water tap in the kitchen, the bath and bathroom sink mixer.

The issue is particularly obvious when showering - we set the desired temperature and will be fine but suddenly the hot water will stop and shower will go freezing - when this happens the pump sounds like it's struggling. Often turning off the hot tap and back on will instantly fix it - it's not consistent sometimes it will be fine for a shower and then others it will be a nightmare. its not just he shower - have the same problem when filling the bath although less obvious.

Anyone any ideas what could cause this?


Sponsored Links
Is the pump fed off of the single pipe that comes out the top of the HW cylinder and then tee's with a pipe running up to the cold cistern, and one down to the pump? If so, you could be getting air bubbles being drawn in by the pump.
Will take A look at that - now you say it it does sound like air in the system when you turn on the taps sometimes

If this is the case is there any way to improve it easily?
Sponsored Links
Depends on your level of expertise I guess as to how easy you may find it.

If it is drawing in air bubbles from the HW cylinder and it isn't being fed from a flange already then installing one may correct it.
A Sussex or Essex (other brands are available) flange is a fitting that is installed into the top or the side of your HW Cylinder and the tube dips into the water in the cylinder some way from the top, avoiding the bubbles that can gather there.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local