What are Shower Pumps?
Shower Pumps are used to improve shower performance where water pressure is an issue, turning a trickle into a rejuvenating forceful shower. Shower pumps can be used with a variety of shower / plumbing systems. With a gravity fed water system a pump can make a substantial improvement to the showering experience and allow extras such as body jets.
Types of Shower Systems
Aqualisa have a guide / diagram to the three types of shower system below:
1. Gravity System
A cold water tank usually located in the roof space, and a hot water cylinder, frequently in the airing cupboard.
2. Combination Boiler System
These systems heat your water as you use it and usually consist of a boiler attached to a wall, often in the kitchen. This is a typical Combi boiler – a multi point heater is a similar type of system. They are usually located in the kitchen and fire up to heat the water the moment you turn the hot tap on.
3. Mains Fed System
(High pressure system or unvented hot water system) A high-pressure cylinder of water, heated by a boiler or immersion heater, usually providing high volumes of water.
Types of Shower Pump
Salamander and Stuart Turner both give advice on the types of shower pump that can be used. Below is an overview of each type:
Universal pumps are fully automatic, will work under both positive and negative head conditions and are suitable for installation into open vented hot and cold water systems. Universal pumps do not require a gravity flow of water to start the pump.
Standard pumps operate under positive head conditions and are suitable for installation into open vented hot and cold water systems. Standard pumps require a minimum gravity flow of approximately 0.6 litres/minute.
Positive head systems (Gravity-fed)
Several different plumbing systems are used in UK homes, the most common of which is a gravity-fed system detailed in the schematic diagram (above and below). In these types of systems there is usually a cold water cistern in the loft with a hot water tank below it, probably in an airing cupboard. If your shower is not forceful enough due to insufficient water pressure, this can be easily boosted by the installation of a pump. The diagram shows where the pump should be situated for gravity-fed systems.
Negative head systems (Gravity-fed)
Negative head systems are where poor natural flow of water goes to the shower head because it is above the height of the base of the cold water tank or there is limited height between the base of the cold water tank and the shower head. Most instances of negative head systems occur in loft conversions or where the cold water tank sits on the joists in the loft.
When the distance between the cold water storage cistern and the shower head is 600 mm or less, or when the natural flow is poor or less than 2 litres per minute of combined hot and cold it is possible a negative head pump may be required.
Twin impeller pumps pump both hot and cold water supplies, one impeller on the cold inlet and one impeller on the hot inlet.
Each impeller on the pump then goes on to supply the outlet, which is commonly a shower valve.
Single impeller pumps simply take one inlet, and that can be cold or hot water, or blended water after a shower or mixing valve.
Typically single impeller pumps can be used to supply single hot or cold taps, electric showers, combination boilers and washing machines. Electric showers and combination boilers need to be fed via a header tank
Pumps are rated in ‘bars’ which is the measure of pressure –1 bar pressure being equal to 10 metres static head of water. The higher the bar rating the higher the performance.
The following can be used as a general guide for applications:
1.0 bar pressure = Low boost
1.5 – 2.0 bar pressure = Medium boost
3.0 bar pressure+ = High boost
Salamander Guide to which Pump
Salamandar has produced a 14 point guide to which Shower Pump for which application around your house:
- To a Combi Boiler : Where mains pressure is low, the supply to the combi boiler can be boosted via a header tank and single impeller pump.
- Instant electric shower :
Where mains pressure is low the supply to an electric shower can be boosted via a header tank and single impeller pump.
- Instant electric water heater :
Where mains pressure is low the supply to an electric shower or water heater can be boosted via a header tank and single impeller pump.
- Washing machine or dishwasher : Boost supply of hot or cold water or both, to ensure continuing pressure of supply.
- Conventional shower : A conventional shower can be boosted depending on the needs of the consumer from 1.5 to 4.3 bar.
- Victorian can shower head : Victorian can shower heads can be boosted by 2.0 bar shower pumps. Large shower heads may need larger pumps – consult PumpWise if unsure.
- Multi-function shower : We recommend a minimum 1.5 bar pump to ensure good performance through the shower head.
- Massage function : Recommended minimum of 1.5 bar pump to ensure good performance through the shower head.
- Champagne spray : Recommended minimum 1.5 bar pump to ensure good performance through the shower head.
- Body jets (4 max) : Recommended minimum 3.0 bar pump to ensure good performance through the shower head.
- Whole house showers : We have a range of house pumps for all household needs such as showers, taps, bath fill and en suite shower rooms.
- Toilets : We recommend 1.5 or 2.0 bar single impeller pumps to boost toilet flush.
- Washbasins : Recommended – twin impeller pumps for monobloc mixer taps or single impeller pumps for single tap supply.
- Individual hot / cold taps or bath : Depending on need, recommended – single impeller pumps from 1.5 bar for basin fill or 3.0 bar plus for bath fill applications.
Shower Pump Advice – More Information
For more information, the manufacturers have a help line who will advise you on the most suitable pump for your individual plumbing / shower pump requirements:
- Salamander Pumps – 0191 516 2002
- Stuart Turner – Pump Assist Team – 0844 980 0097
- Aqualisa Customer Helpline – 01959 560010
Click to view the complete range of Shower Pumps available from Trading Depot.