QUESTION: I want to save on chemicals to treat my pool and spa and I thought about installing an electric ozone purifier. Is ozone safe to use and is this going to cost more to operate than using chemicals?ANSWER: Ozone gas is an effective alternative to chlorine chemicals in swimming pools and spas. Although you have heard about smog and ozone alerts in the air in major cities, ozone gas in water is quite different. Many municipalities use ozone gas to purify their drinking water.Ozone in the air from factories and other sources combines with other pollutants in bright sunlight to cause visible and unhealthy smog. The small concentration of ozone gas in pool water quickly converts back to plain oxygen when it leaves the surface of the water.The ozone has no negative effect on your skin in the water as chlorine sometimes can.Even if you install an ozone purifier, you will still need to use some chemicals in your spa and pool. Generally, the amount of chemicals needed is reduced by more than 50 percent.Ozone also reacts with chlorine residual chemicals to release additional free chlorine for a greater savings.Once in the water, ozone gas attacks bacteria, viruses and other contaminants by oxidation similar to how chlorine works. Ozone also causes the neutralized contaminants to coagulate into larger particles.They are still microscopic, but this makes it easier for the filter to remove them.The electricity cost to operate an ozone purifier depends upon the size (ozone output) of the system and its design. Typically though, they use less electricity than a 60-watt light bulb and operate silently. Also, they operate only when the filter pump is on or by an automatic timer.Overall, using an ozone purifier will cost less than using chemicals alone.There are two designs of ozone generators. One uses a corona discharge method. Inside the unit, an electrical spark in the air converts plain oxygen into ozone.The fresh odor outdoors after a thunderstorm is the ozone gas created when the lightning (large sparks) occurs in the sky.The other design uses ultraviolet light inside the generator.Strong UV light converts oxygen into ozone. UV models are effective and cost less initially than corona discharge models, but they use more electricity.Currently, corona discharge models are more popular. They produce a higher ozone concentration and work well in large pools.Instead of adding chlorine chemicals, electric units are available which break down salt into chlorine. The level of salt in the water is less than a human tear. Some ozone models include a salt chlorine generator.The following companies offer ozone pool/spa purifiers: Clearwater Tech. (800-262-0203 www.cwtozone.com), Del Industries (800-676-1335 www.delozone.com), JED Engineering (800-552-8838 www.jedengineering.com), Lifeguard Purification (800-678-7439 www.lifeguardsystems.com), and Prozone (256-539-4570 www.prozoneint.com).Send inquiries to James Dulley, Butler Eagle, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit www.dulley.com.

QUESTION: I have a gas furnace and I could swear I feel cold air coming out of the registers sometimes last winter. The house seemed to stay plenty warm though. Was this just my imagination or can it really happen?ANSWER: It is not just your imagination. Due to pressure differences throughout your home, air may be drawn through the ducts when the furnace is off. Even if this air is 80 degrees or more, it will feel cool to your skin.Heating ducts are usually run up outside walls under windows. The duct takes up some space for insulation, so slow-moving air can lose its heat quickly. This might happen when the furnace first starts or stops.