FAQ
Frequently Asked Questions
Got a question about UVbless?
Do you need advice about a unit, lamp, spare part or how UVbless actually works?
Here are some frequently asked questions, but if you can’t find the answer to your question then please do not hesitate to contact us.
How did UV disinfection works?
UV disinfection uses ultraviolet light to inactivate bacteria, viruses, and other microorganisms in water, air, or on surfaces. The UV light damages their DNA or RNA, preventing them from reproducing and causing harm. As microorganisms pass through a UV system, they are neutralised quickly and safely, without the use of chemicals. When properly designed, UV systems can achieve up to 99.99% disinfection efficiency.
Where should I install a UV unit?
A UV unit should be installed as close as possible to the point of use, such as taps or appliances. For a single outlet, this is typically under the sink, ensuring water is disinfected just before use and minimising the chance of recontamination.
For multiple outlets, the UV unit should be placed at the final point before the pipework branches, supplying all connected outlets. The same principle applies to commercial systems: positioning the unit near the end of the system provides the most effective protection.
Why do I need a pre-filter with a UV unit?
A pre-filter removes fine particles and sediment from the water before it enters the UV unit. These particles can shield microorganisms from UV light or create shadowed areas, reducing the effectiveness of disinfection.
By removing suspended solids in advance, the UV system can deliver the intended UV dose evenly, ensuring reliable and consistent disinfection performance.
How does UV affect Legionella?
UV disinfection inactivates Legionella by damaging its DNA, preventing the bacteria from reproducing. When water passes through a properly designed UV system, Legionella is neutralised quickly and effectively, helping to reduce the risk of contamination without the use of chemicals.
How often should I change my filter?
Filter replacement intervals typically range from every 2 to 6 months, depending on water quality and usage. A noticeable drop in water pressure is often a sign that the filter is clogged and should be replaced to maintain proper system performance.
Does UV kill everything?
Not all microorganisms respond to UV light in the same way. While UV consistently damages DNA, some organisms have protective structures that make them more resistant to UV exposure.
Most common bacteria and viruses are effectively inactivated by standard UV systems, while more resistant forms, such as bacterial spores, may require higher UV doses or specialised UV designs to achieve effective inactivation.
Why would I need to treat mains water with UV
Municipal tap water is treated by local water authorities to meet established safety and quality standards and is generally safe for everyday use. For those seeking added peace of mind, ultraviolet (UV) disinfection offers an additional layer of protection.
UV technology effectively inactivates a wide range of microorganisms that are known to be less responsive to traditional chlorine disinfection, including Cryptosporidium, Giardia, mycobacteria, Legionella, as well as viruses such as adenoviruses and rotaviruses.
While UV systems do not replace municipal water treatment, they serve as a powerful complementary solution, helping to further reduce the risk of microbial contamination and enhance overall water safety.
Will UV change my water?
Under normal operating conditions, UV disinfection does not alter the mineral content or chemical composition of water. It is a safe, chemical-free treatment method that leaves no residuals. Only under extremely high intensities or in specialized industrial applications may UV light trigger certain photochemical reactions, such as the degradation of specific organic compounds in water.
Standard UV systems work by inactivating microorganisms such as bacteria and viruses. They typically do not affect the taste, odor, or appearance of the water. As a purely physical treatment process, UV disinfection provides no residual effect once the water leaves the system.
What is UV transmission?
UV transmission (often referred to as UVT or T10) describes how much ultraviolet light can pass through a liquid, typically measured over a 10 mm path. It is expressed as a percentage, with higher values indicating clearer water that allows UV light to penetrate more effectively.
Water with a higher UV transmission is easier to treat, allowing for higher flow rates or more compact and energy-efficient UV systems. Lower UV transmission can still be treated effectively but usually requires higher lamp power or a different reactor design.
What is shadowing?
Shadowing occurs when suspended particles in water block UV light, creating areas that UV cannot reach. Microorganisms can attach to or hide within these particles, reducing their exposure to UV and limiting disinfection effectiveness.
This is why filtration is used before UV treatment. By removing particles that cause shadowing, microorganisms are fully exposed to UV light, allowing the system to deliver consistent and reliable disinfection.
Do I need an over-temperature safety sensor for my UV unit?
An over-temperature safety sensor (TSS) monitors the water temperature inside a UV system. It is particularly important for applications with intermittent or low flow, where water may remain in the UV chamber while the lamp is operating.
If the water temperature rises above a safe level, the sensor automatically switches off the UV lamp to prevent overheating and potential damage. Once the temperature returns to normal, the system resumes operation, helping to protect both the equipment and the user.
How often should I change my UV lamp?
Most UV lamps are designed to operate for around 9,000 hours, which is typically 12 months of use. Although the lamp may still appear to be working, its UV output gradually decreases over time and may no longer deliver the required disinfection dose.
For reliable performance, UV lamps should be replaced annually. Many UV systems include a lamp-life warning, but planning a yearly replacement helps ensure consistent protection.
Chenzi high-quality UV lamps are engineered with optimized materials and advanced manufacturing processes, delivering an extended service life of up to 12,000 hours.
Does a UV system require electricity to work?
Yes. UV systems require a continuous power supply to operate the lamp and control components. Without power, the system cannot provide disinfection.
Can UV systems be used for rainwater or well water?
Yes. UV systems are commonly used for rainwater harvesting and well water. Pre-filtration and proper system sizing are essential to ensure effective treatment.
Can UV systems be used in commercial or industrial applications?
Yes. UV technology is widely used in commercial and industrial settings, including food processing, healthcare, and manufacturing, where high hygiene standards are required.
Does UV provide residual protection?
No. UV provides disinfection only at the point of exposure. Once water leaves the UV chamber, there is no residual effect, which is why correct installation and system design are important.