UV water purification passes water by an ultraviolet lamp that inactivates bacteria, viruses and other germs without adding chemicals or changing the taste. It is popular where the supply is uncertain: borehole water, rainwater tanks, dams and rural taps. It only works on clear water, so a pre-filter is normally part of the set-up. Whether you want to treat the kitchen tap or the whole property, send one request and local installers quote you directly. It is free and there is no obligation.
What UV does, and what it does not
UV light damages the genetic material of germs so they cannot multiply. That is all it does. It does not remove sand, rust, hardness, salts, nitrates, chlorine or chemicals, and it leaves no disinfectant in the pipes after the lamp. Cloudy or coloured water blocks the light, so the unit must be fed with clear water.
That is why UV is almost always paired with a sediment filter and sometimes with carbon, softening or reverse osmosis. For a borehole, test the water first. See borehole water filtration.
Sizing and where to fit it
A UV unit is sized by flow rate and by how clear the water is. Tell the installer how many litres a minute you need, the pipe size and the pressure. Small units suit one drinking tap; larger ones treat the water going to a whole house. Common choices:
- Point of use: at the kitchen sink, treating drinking water only.
- Point of entry: after the tank or pump, treating all the water that enters the house.
- Rainwater and dam water: a sediment filter first, then UV, as the water often carries leaves and silt.
Fit the unit after the filter and as close as possible to where the water is used.
Lamps, power and upkeep
A UV lamp wears out even if it still glows, so the lamp is normally replaced about once a year. The quartz sleeve around it should be wiped clean on a regular schedule, as scale and film cut the dose. Ask for a unit with an alarm or an indicator for lamp failure. The unit runs on 230 V, and a lamp that is off during a power cut treats nothing, so water that flows through while the power is out is not treated. Consider a small backup supply or a bypass valve, and a service plan from your installer.
Cost and comparing quotes
A small home UV unit costs about R1,150 to R4,000. Whole-property and commercial units cost more, and are quoted per site. Add the pre-filter, fittings and installation. Compare the flow rate each unit handles, the lamp life, the price of the replacement lamp and sleeve, the warranty and the service offered. Then see how the unit fits with a water purifier or a full filtration train. The lowest price is not a bargain if the lamp is hard to find.
What to include in your request
- Water source: borehole, rainwater, tank or dam
- Flow rate you need and the pipe size
- Whether the water is clear or cloudy
- Drinking tap only or the whole property
- Power supply and any backup you have
UV Water Purification for different sites
- Households: a small UV unit at the kitchen tap or after the tank for drinking water
- Offices and business parks: UV on the incoming line of a rural office or workshop with a tank or borehole supply
- Schools, crèches and colleges: UV after the storage tank at a rural school, with the lamp changed in the holidays
- Clinics, practices and care homes: UV as an extra step on filtered tank or borehole water, with lab tests on a schedule
- Lodges, hotels, restaurants and events: UV treatment for a lodge or guesthouse drawing from a borehole, dam or rain tanks
- Factories, mines and building sites: UV on process or canteen water after sediment filtration, sized to the line flow
- Shops, gyms and refill stations: a small UV unit for a farm stall, deli or salon on tank or borehole water
- Farms, smallholdings and villages: UV after a sediment filter on dam, rainwater or borehole supply for the homestead
Frequently asked questions
Does UV remove chemicals or salts from water?
How often must the UV lamp be replaced?
Can UV treat rainwater and tank water?
Do you supply UV systems?
UV Water Purification by province and city
- Johannesburg
- Pretoria
- Centurion
- Midrand
- Sandton
- Randburg
- Roodepoort
- Krugersdorp
- Randfontein
- Germiston
- Boksburg
- Benoni
- Kempton Park
- Alberton
- Vanderbijlpark
- Vereeniging
- Durban
- Pinetown
- Pietermaritzburg
- Richards Bay
- Newcastle
- Ladysmith
- Gqeberha (Port Elizabeth)
- East London
- Kariega (Uitenhage)
- Mthatha
- Cape Town
- Bellville
- Paarl
- Stellenbosch
- George
- Worcester
- eMalahleni (Witbank)
- Middelburg
- Secunda
- Mbombela (Nelspruit)
- Rustenburg
- Brits
- Klerksdorp
- Potchefstroom
- Mahikeng
- Polokwane
- Tzaneen
- Kimberley
- Upington
- Bloemfontein
- Welkom
- Sasolburg