Many homes in the UK experience low water pressure, which can reduce water flow to a trickle, meaning it can take ages to fill a kettle, toilet cistern or bath.

                 The solution to low water pressure! image 1           

Unfortunately, this can be caused by many things. For example, if you have a mains fed water system, your pressure can be affected by how much water other people in your house are using at the same time, or even if your home is at the top of a hill, as water companies rely on gravity to get water from a reservoir to your home.


If you have a heating and hot water system that relies on gravity to move water around the home, while fine for most household needs, a gravity fed system rarely provides enough pressure to give powerful, invigorating showers or quick bath-fills.


The difference a pump can make


A shower pump can often be the perfect solution to boosting water performance if you suffer from poor water pressure in your home. The results from installing one of these devices include improved shower performance, a quicker bath fill, and strong, flowing taps.


The images below depict the flow rate exiting a normal shower head, both with and without using a shower pump:


            The solution to low water pressure! image 2 - Without a pump
Without a pump
       The solution to low water pressure! image 3 - With a pump
With a pump

However, it is important to make sure that you get the right pump for your heating system. If you are unsure of which water system you have, please take a quick read of our Household Water Systems article.




In the UK, a lot of homes have a heating and hot water system that relies on gravity to move water around the home. This type of plumbing system is called a gravity fed system. Whilst perfectly adequate for most households' needs, gravity fed systems rarely provide enough pressure to give a powerful, invigorating power shower or quick bath-fill, and that’s where shower pumps come in to give this a much-needed boost.


Do you need a positive head or universal pump?


Where the cold water tank is located affects the type of pump you'll require.


For gravity fed systems, the gap between the bottom of your cold water storage tank and the highest point in your pipework (or highest outlet) will determine whether your gravity fed system is positive or negative head. Positive head pumps will only work on positive head systems. Universal (negative head pumps) will work in both situations, so if you are unsure, we'd recommend you choose a universal pump to be on the safe side.


The general rules of thumb to follow are...


You have a positive head system if you have more than 600mm from the bottom of your cold water storage tank to the highest point in the system aft the pump:


            The solution to low water pressure! image 4           


You have a negative head system if your outlet or highest point in the pipework after the pump is above, or in line with, the 600mm point below the cold water storage tank:


            The solution to low water pressure! image 5           



Do you need to pump to the shower only, or additional outlets (i.e. bath taps, toilet cistern or washing machine)? As a guide, the table below should help:


I want to boost:Gravity Fed Positive HeadGravity Fed Negative Head
Shower only with a shower head of 100mm–120mm1.5 bar twin positive head pump1.5 bar twin universal pump
Small bathroom and a shower with a shower head of 100mm–120mm2.0 bar twin positive head pump2.0 bar twin universal pump
Larger bathroom or multiple smaller bathrooms with a shower head of 120mm+2.0 bar twin positive head pump2.0 bar twin universal pump
Multiple bathrooms, 150mm+ shower heads and/or shower with massage function and body jets3.0 bar twin positive head pump3.0 bar twin universal pump


Are you pumping both hot and cold water supplies?


In most cases, you will be looking to boost both hot and cold water supply within your home.


Twin impeller pumps are designed to supply both hot and cold water to showers, bathroom and whole house installations.


Single impeller pumps are designed to supply hot or cold water, either to single or multiple outlets. This can often be when the cold water is mains fed (therefore stronger) and the hot needs boosting to match this pressure.


Which pump should I choose?


Salamander Pumps have two pump ranges suitable for boosting shower performance in a gravity fed system: CT Pumps and Right Pumps.


The Salamander CT Range of shower pumps are long-lasting, hard-working, compact and easy to install. In this range of best-selling models:



  • The Salamander CT Xtra shower pumps are suitable for positive head installations only and are available as twin or single ended, 1.5 or 2.0 bar.


  • The Salamander CT Bathroom pumps are designed to boost hot and cold water to appliances within the entire bathroom. Available as positive or universal heads up to 2.6 bar.


  • The Salamander CT Force range has robust brass ends and brass impeller, with a higher quality finish. They come in both universal and positive head variants and will boost the shower, bathroom or whole house up to 3.0 bar.



The Salamander Right Pump range of pumps have a centrifugal impeller, allowing them to move water very quietly and offer maintained pressure at increased flow rates. Suitable for boosting the shower bathroom and whole house, these are available in positive and universal heads up to 3.0 bar. Of particular note, the Salamander RP50PT pump has been independently verified by the University of Salford as being one of the quietest pumps in the UK while operating – at just 45.5dB!




If you have a combi boiler in your home, your system is instead mains fed and relies on the local water authorities to provide water to your property boundary. This means that your water pressure may vary at different times of day, e.g. when your neighbours are also using water too, or you may constantly have less water pressure and flow than you would like.


Salamander Pumps offer a mains water booster pump called the Salamander HomeBoost Mains Water Pump, which fits directly onto your incoming mains pipework. This product legally boosts water performance either directly or indirectly via your combi boiler up to 12 litres per minute (and pressure up to 1.5 bar too).


Read more about this particular pump in our dedicated HomeBoost article.


You can improve water performance in an unvented system using a break tank and shower pump. We recommend speaking to a member of the Salamander Technical Team on 0191 5162002 or a local plumber before making a purchase.


Need any other advice? Please don't hesitate to contact us.