Any water source can become contaminated by microorganisms. Unfortunately, the microbiological quality of your water supply can change due to environmental conditions. By providing your own treatment, you are taking responsibility for ensuring the quality of your water supply for you and your family.
Yes, UV is known to be an effective technology to inactivate these microbes which are highly resistant to chlorine disinfection. In addition, the UV dose level required to inactivate these cysts is relatively low, at 10 mJ/cm2 for 99.9% reduction. Recommended flow rates for VIQUA UV systems are based on a UV dose level of 30 mJ/cm2. (See ‘What is UV dose?’)
Yes, E. coli requires a UV dose of 6 - 10 mJ/cm2 to achieve 99.99% reduction. As noted, VIQUA UV systems use a UV dose of 30 mJ/cm2 (@ 95% UVT) as the basis for flow rate sizing. (See ‘What is UV dose?’)
UV dose or fluence is the amount of UV energy imparted to the water as it flows through the system. It’s related to UV lamp wattage but also how well the UV is transmitted through the water, which is measured as UVT. (See ‘What is UVT?’)
UVT is the proportion (%) of the UV energy from the lamp that can penetrate water flowing through the UV system. Water quality varies and this affects UVT. Turbidity in the water reduces the transmission of light while contaminants that give rise to colour (for example, in lake water) reduce UVT due to absorption of the light. Water drawn from a dug well or surface source (lake, river) may have UVT in the 55% - 80% range, while water drawn from a drilled well typically has UVT in the 85% - 97% range. Published flow rates for VIQUA systems are based on water with UVT of 95%, except for NSF-validated systems which use UVT of 70% as the basis for flow rate calculation. Different levels of UVT can be accommodated by sizing the UV system accordingly.
All VIQUA systems are equipped with “lamp-out” monitors which indicate lamp status. Monitored systems equipped with a UV sensor indicate the amount of UV that is being imparted to the water and will go into alarm if the UV dose is insufficient.
Municipal or city water originates from a water treatment facility, and water quality is regulated by health authorities. However, once the water has left the treatment facility, it moves through an aging and crumbling infrastructure system which can lead to contamination. There are also occasions when circumstances lead to “Boil Water Advisories”. If you wish to provide your family with added peace of mind, then a UV system is an affordable insurance policy against the possibility of drinking water contaminated with microbes.
UV systems are very economical to operate. A typical whole house UV system uses the same power as a 40-Watt light bulb.
No, UV is a physical process, so it does not add anything to or change the taste/odour of the water. It simply provides reliable treatment without the use of chemicals. In rare circumstances, untreated sulphur odour can become more noticeable after UV treatment.
No, the UV system should be left on whether you are using the water or not. By leaving the unit on, you will eliminate the potential problem of having contamination pass through the system while the unit is off. However, if water is drained from your system (e.g. winterizing), your UV system must be turned off.
UV lamps have a useful life of approximately 9000 hours, which means that the lamps require annual replacement in a full time residence. The UV light will be illuminated beyond one year, but there may not be enough UV energy to provide optimal performance. There is a quartz sleeve that surrounds the UV lamp which must be kept free from hardness or iron deposits by cleaning with a lime removing solution and soft, lint-free cloth. Proper maintenance of any installed pre-treatment equipment is also required.
Yes, for UV to be fully effective, water quality parameters should be as follows:
Note: If you are unsure of the quality of your water supply, it is important to have the water tested. A UV transmittance test (UVT) is strongly recommended for surface/shallow well sources or water that is even slightly coloured. To find out more information about UVT tests, please contact VIQUA or your local water treatment specialist.
Yes. Microbes can potentially be shielded by suspended particles (turbidity) in the water supply, so it’s necessary to filter the water to remove these particles. A high quality filter system with a rating of 5 microns is recommended. Filtering to a lower micron rating (for example, 1 micron) will remove smaller (fine) particulates but can result in undesirable restriction of water flow. Several VIQUA UV systems incorporate pre-filtration for easier installation and maintenance.
The most important consideration is not to install a UV system in situations where the recommended maximum water flow can be exceeded. In situations where this is a possibility, flow restrictors are available to prevent that from happening. The best approach is to choose a UV system that is sized appropriately for the maximum possible flow (present and future) of your water supply equipment.
Although not essential, the installation of simple by-pass plumbing allows for emergency use of the water in case the UV unit is required to be removed from service. A simple by-pass assembly with three isolation valves can be installed easily.
No, UV systems are designed with inlet/outlet ports correctly sized for the specific application. Whole home systems typically have 3/4” or 1” connections, while smaller point of use options have 3/8” or 1/2” connections.
VIQUA offers different models to suit widely varying water flow demands. An average whole home UV system ranges in size from 5 to 12 GPM. Determining the maximum flow rate of your pump will determine the UV model best suited to that flow rate.
It is important to not undersize the UV system. If in doubt, it’s always better choose the next largest size.
As the UV lamp and/or sleeve need to be periodically removed from the reactor chamber, you must allow at least double the length of the chamber to facilitate removal.
VIQUA systems incorporate proprietary electronic controller technology, which provides constant output voltage regardless of variations in input frequency or voltage, providing consistent UV output. However, in regions that experience significant power fluctuation, the use of high-quality surge protection is recommended. UV systems should always be connected to a dedicated electrical outlet protected by a GFI (ground fault interrupter).
The chamber that carries the water flow is manufactured from passivated stainless steel. Both the UV lamp and the surrounding sleeve are manufactured from high purity fused quartz (not plain glass). All seals that come into contact with the water are FDA and NSF compliant.
Stainless steel chambers are warranted against leakage due to manufacturing defect for 10 years. System controllers are warranted against manufacturing defect for 3 years (5 years for PRO series, H & K variants), while UV lamps, quartz sleeves, and UV sensors are covered for 12 months.