Ultra-Violet Water Filtering

A great deal of calls recently have been questions about ultra-violet or UV water filters. The majority of those calls concern residential applications such as under-sink and whole-house roles. But a handful of them are asking about using UV for commercial purposes. Specifically, sanitizing fruit juices.

Orange juice, grape juice and the like all have color to them. When flowing through a pipe, even a glass tube, if you cannot see through the tube, then neither can the ultra-violet rays. They will do nothing to kill bacteria under those circumstanses.

That being said, let's look at what UV is good for. It is a highly efficient destroyer of bacteria. The bacteria in water passes through one of these quartz tubes and is exposed to 16,000 microwatts seconds/cm2 of ultra-violet, effectively killing them. Your sterilized water can then pass through a filter, removing the now harmless critters.

The UV bulb will need replacing about once per year and is very simple to change. The filter configuration varies from model to model but most come with a post-carbon filter and some with a pre-sediment filter. The filters should be changed about every 6 months depending a lot on the condition of your water. It's a simple process to monitor your post-filter for clogging or a drop in flow rate. Always have an extra filter or two on hand.

Water Value has whole-house Pura® filters available here, but there are also some 1 and 2 gallon-per-minute UV filters made by Pura®. They are designed for use under the kitchen sink. They may also be used in the water line leading to your refrigerator/icemaker.

UV lamps do not use chemicals to treat your water so they are ideally suited to applications where the backwashing and draining by other filters is undesireable.

The Pura® UV20 filters sense water flow and activate the UV lamp only when needed. While a UV bulb does use a fair amount of electricity, it is still less expensive than operating most chlorine systems.