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UV Sterilizer Size Calculator
Quick answer: A UV sterilizer must be rated for the highest flow that passes through it. Convert litres per minute to US gallons per minute (÷ 3.785), add a margin, and choose a UV rated at or above that figure. Too much flow through a small UV means water passes too fast to be disinfected properly.
Key facts
- Size by peak flow, not daily volume
- GPM = litres per minute ÷ 3.785
- Add a margin and choose the next size up
- Clear, pre-filtered water is essential
On this page
UV Size Calculator
Example figures only: replace them with your own. Results update as you type.
Flow in US gallons per minute–
Choose a UV rated at least (GPM)–
Flow in m³ per hour–
How to Find Your Peak Flow
Time how long it takes to fill a 20-litre container at the fullest flow, or use the pump's rated flow. For a refill station, use the flow of all nozzles running at once.
H-TECH UV Sterilizers by GPM
| Product | Price |
|---|---|
| H-Tech 0.4GPM 6W UV Sterilizer | KSh 5,000 |
| H-Tech 0.65GPM 10W UV Sterilizer | KSh 5,300 |
| H-Tech 1GPM 12W UV Sterilizer | KSh 6,000 |
| H-Tech 2GPM 16W UV Sterilizer | KSh 11,600 |
| H-Tech 6GPM 25W UV Sterilizer | KSh 13,000 |
| H-Tech 12GPM 55W UV Sterilizer | KSh 40,000 |
| H-Tech 20GPM 80W UV Sterilizer | KSh 45,000 |
| H-Tech 26GPM 110W UV Sterilizer | KSh 52,000 |
| H-Tech 43.86GPM 165W UV Sterilizer | KSh 68,000 |
| H-Tech 65GPM 220W UV Sterilizer | KSh 85,000 |
Current listed prices incl. VAT (updated 4 October 2026).
Make UV Work
- Filter the water first (5 micron, then 1 micron) so particles do not shade microbes: micron ratings.
- Clean the quartz sleeve and replace the lamp about yearly.
More: UV sterilizer guide.
Watch: RO purifiers and water ATMs
Frequently asked questions
How do I size a UV sterilizer?
By the peak flow in GPM, plus a margin; choose a UV rated at or above it.
How many litres per minute is 1 GPM?
About 3.8 litres per minute.
What happens if a UV is too small?
Water passes too fast to receive enough UV dose to be disinfected properly.
Do I need a filter before UV?
Yes, clear, pre-filtered water is essential for UV to work.