Pro Active Mechanical, Inc.
2400 E. Main Street
Saint Charles, IL 60174
Phone: (630) 514-5431
One Engineers Opinion
“Why use Ultraviolet lamps when Needlepoint Bi-polar Ionization is better?”
Many Contractors use Ultraviolet lamps attempting to keep cooling coils and drain pans clean. Cooling coils and drain pans are wet, cold and dark. This makes the perfect breeding ground for bacteria. When bacteria grow on the coil fins, it reduces heat transfer and increases air pressure drop through the coil. As the bacteria builds up the condensate drain will get clogged.
Over 20 years ago, we began using ultraviolet lamps to keep coils and drain pans clean. The lamps do a good job but the lamp replacement is an ongoing expense for the owner. One difficulty with the UV lamp technology is that it is only effective “kills” in “the-line-of-sight”. If the UV lamp doesn’t “see” the bacteria, it cannot kill it. If the UV lamps are on one side of the coil, bacteria can still grow on the dark side of the coil. However the use of UV lamps has been effective for many years.
Five years ago needlepoint bi-polar ionization became available. Bi-polar ionization generators have been around since Albert Einstein invented the first one. However, the older style bi-polar ionization generators used perishable glass tubes and they also generate ozone as a byproduct of the ion generation process. Needlepoint bi-polar ionization units have been tested in accordance with UL 867 and proven to keep ozone levels seven times lower than allowed by the EPA. This is a benchmark that glass tube ion systems cannot meet.
Because needlepoint bi-polar ionization units are so small they can easily mount at the furnace fan inlet. Mounting the devices in this location has many advantages. Ions flow from the fan through the DX coil. Ions kill bacteria so the coil and drain pan are kept clean. The ions then sanitize the duct system as they flow through it. Then the ions enter the occupied space where they do many things that improve the space Indoor Air Quality [IAQ].
Figure 1 : Needle Point Bi-polar Ionization
As you can see the needlepoint bi-polar ionization does many good things for the HVAC unit, duct system and occupied space that Ultraviolet lamps do not. This technology will improve the home owner’s or building owner’s Indoor Air Quality much more than UV lamps. Other benefits are that the power requirements are so low that the ion generators can be powered from the 24 volt control voltage already available at the furnace or fan coil. Also the ion generators do not have lamps that have to be replaced annually so there are no replacement parts and no maintenance. Unlike a UV light, needlepoint ion generators can be touched and viewed while operating without fear of shock, skin or eye damage. The ion output will not affect any insulation, wires or other organic materials in the air stream, which are usually affected by UV light.
With the ions ability to kill viruses and bacteria in the air and on surfaces, the occupants will have a reduced occurrence of illness being transmitted. Independent test data provided by EMSL Laboratories for one needlepoint bipolar ionization manufacturer that showed astonishing pathogen kill rates in a 10’ x 10’ x 10’ space and below is the summary:
MRSA / Staph – 96.24% in 30 minutes
TB – 69.01% in 60 minutes
E.coli – 99.68% in 15 minutes
Because ions reduce mold spores ability to reproduce, potential mold growth is almost eliminated. In another independent study, mold spores were reduced by 97-99% in a space that had already been professionally remediated for mold! Before the needlepoint ion generator was activated, the mold spore count was well over 300,000 spores per cubic centimeter!
Ions also attach to the surfaces of allergens. This reduces the affect allergens have on the space occupants.
Ions also break-down many other Contaminants of Concern (COC). Some contaminants are ammonia, formaldehyde and odor. I have been involved in retrofit projects where odors from sewer gas and dumpster smell were eliminated. Because the ions control COC’s, the technology can be combined with ASHRAE 62’s IAQP and outside air may be reduced on many new and retrofit projects.
Basically, in my opinion Ultraviolet lamps were good in their day. However, today needlepoint bi-polar ionization is the better choice for home owners and building owners.