Low Water Pressure Boosting
Dribbly shower? Bath takes ages to fill? Read on.
So you’ve decided now may be the time for that hot tub you’ve always wanted. Perhaps you are fed up with standing under the dribble from your shower or you really want to splash out and turn the vegetable patch into a swimming pool?
You may need to stop for a minute and think about your water supply.
Can your current system handle more load or is it going to need a little help? Do you have low mains pressure? This article should help you decide what you might have to consider.
Low mains water pressure can affect all sorts of things in the home, including showers, sprinklers, additional bathrooms, appliances, decorative fountains, swimming pools or even simply how long it takes to fill the bath.
In most cases a pump will form part of the solution. In concert with pressure vessels, water tanks, butts and other equipment, most domestic water pressure issues have a simple and cost-effective solution.
How do you increase low mains water pressure?
Different methods for increasing your low water pressure apply depending on where you want increased pressure, your existing system (including any boilers installed) and what you want to do.
When we talk about mains water pressure boosting there are two different measurements for concern:
- Water pressure
- Flow rate
Water pressure is a measure of the force that pushes water through the mains and into your pipes. It is measured in ‘bars’ – one bar is the force needed to raise water to a height of 10 metres. The amount of pressure at your tap depends on how high the reservoir or water tower that supplies you is above your home, how close you live to one of your supplier’s pumps or on how much water is being used by other people in your neighborhood.
Water flow rate depends on the size of your pipe. If several taps or appliances are connected to the same pipe, there will be a lower flow rate and there may not be enough water coming through the pipe for all of them.
Older houses typically have ½ inch (12.5mm) diameter water supply pipes which can cause problems especially in houses converted into flats. Modern houses and flats usually have bigger pipes – 1 inch (25mm) diameter, enabling higher flow rate and allowing several appliances to be used at once.
Most domestic water companies aim to provide pressure of around 1 bar and flow rate of around 9 litres per minute in the pipe connecting the mains water to your house.
Why do you want to increase your water pressure?
Some of the most common reasons for concern about low water pressure in the home are listed below:
- Low pressure at taps – I want a quicker running bath or better pressure at the taps
- My shower is weak – I want to fit a power shower or increase the water pressure of my existing one
- My garden needs watering – I want to use a hose or sprinkler and increase outside use
- Will my water system cope with a pool – I want to install a swimming pool or hot tub
- Adding an en-suite or additional bathroom
Below are some of the things you need to find out before you start, what you may have to think about, and some suggestions for types of pump that may be part of a suitable mains pressure boosting solution.
Low pressure at taps
Low pressure or flow at the taps can be caused by a number of things depending on if it is cold, hot, upstairs, or downstairs and the type of hot water system you have.
Upstairs – most upstairs taps are fed by gravity from a water tank which typically sits in your attic. Low flow here can be due to the tank not being high enough, pipes being restricted (build-up of limescale) or a supply valve being restricted (limescale or partially closed).
Downstairs – kitchen tap and possibly other taps including washing machine/dishwasher supplies close to your internal stopcock may be fed directly off the mains supply so usually will have good pressure and flow rate. Other cold taps will usually be fed from your cold water tank but again due to the height of the tank these should have good pressure.
Hot water supply at your taps depends on whether you have an older cistern fed system, which has a boiler and separate hot water tank, or a more modern mains fed system (such as combi-boiler) which has no separate hot water tank.
The pressure in cistern fed systems is affected by the height between the tap and your hot water tank in a similar way to cold water from a roof tank.
The pressure in a mains-fed system is dependent on your mains pressure.
My shower is weak
A weak or dribbly shower is no fun – if you want to boost the mains pressure of an existing shower or you want to install a new shower there are a number of considerations depending on the type of shower and what type of hot water system you have:
Simple removable option – the shower is pushed on to the bath taps, pressure is limited to that coming out of your taps. If you have a gravity fed system using a hot water tank the shower pressure will be reduced the further up the wall you mount the shower head. Pressure can be increased by incorporating a pump between cold or hot water tanks and the taps. If you have a mains-fed system such as combi-boiler you should have good pressure. Note that any increase in pressure may make this type of shower unsuitable as it could just dislodge the fittings off the tap.
With a simple mixer built on to bath taps, pressure is limited to that coming out of your taps. If you have a gravity fed system using a hot water tank the shower pressure will be reduced the further up the wall you mount the shower head. Pressure can be increased by incorporating a pump between cold or hot water tanks and the taps. If you have a mains-fed system such as combi-boiler you should have good pressure. An increase in pressure by pumping should cause no problems as it cannot slip off taps like push-on mixer showers.
Wall mounted units which mix cold and hot water supplies usually have separate pressure and temperature control. Ideal for mains-fed systems, if used on tank fed systems you may experience low pressure, however a pump can be added to increase pressure.
Wall mounted units which mix cold and hot water supplies like a manual mixer but boast a thermostatic control ensuring temperature and flow should remain constant even when other taps in the house are being used. Ideal for mains-fed systems, if used on tank fed systems you may experience low pressure, however a pump can be added to increase pressure.
A single unit containing an electric pump which controls the water pressure and temperature. This type of shower uses water supply from a cold water cistern and a hot water cylinder. Water pressure is usually good and only limited by the power of the integral pump/heater. This is not usually suitable for the addition of an external pump.
A single unit which heats water electrically. It is plumbed into a mains cold water supply. An electric shower needs good supply pressure and output pressure reduces as heat increases. Output pressure is limited by supply pressure and the power of the water heater in the shower unit. If the cold water supply pressure to the unit is too low a pump could be added to raise supply pressure to the required value, but otherwise it is not really suitable for the addition of external pump.
If you would like to discuss your specific mains pressure boosting requirements further then don’t hesitate to call our friendly team here at Express Softeners. With over 15 years’ experience and a huge range of pumps, spare parts, pipe work, fittings and control equipment, our skilled staff can give you fast on-site service when you need it.