[LazyPup]

If you are dealing with severe allergies i would recommend a three part filtering system.

1.As a primary filter a Good quality disposable filter pack with a very low merv rating. I would not recommend HEPA filters because from my experience they tend to be a bit on the expensive side, therefore people are reluctant to change them. Rather than that, i would recommend high quality inexpensive disposable filters and change them often. The primary filter removes all the heavy airborne particulates. (The dust you can see with the naked eye.)

2. An electrostatic filter (Electronic). It will remove smoke, airborne chemical vapors and micofine dust particles that are nearly invisible to the naked eye. As the dust particles pass through the grids the dust is electonically ionized, then it is electromagnetically pulled out of the air as it passes the second grid. These units typically have a very low power consumption and only require occassional maintenance, which may involve emptying a dust collector or wiping the grids. It is a DIY maintenance proceedure and does not require the services of an HVAC tech.

3. An Ultra-violate sanitizer. The ultra-violate sanitizer is basically just a special type of flourescent light fixture which is mounted inside the duct work. They require a special type mount that has a safety switch to insure the lamp turns off if the access door is open to prevent damaging your eyes. The UV energy literally kills bacteria and micro organisms in the same manner as sunlight does. While the UV sanitizer is electrically operated it is a very low wattage consumption, typically about 20 to 30 watts. Maintennce: Requires occassonally changing the flourescent tube in the same manner as a conventional flourescent light fixture- expect about the same service life as you would expect from a regular flourescent light)

This three stage filtering system is what is commonly installed in large commercial systems in hospitals, especially in surgical suites, cardio-pulmonary units and nurseries. When installed and operating correctly you can expect to throw your dust cloths away.

Personally, I have been servicing HVAC equipmant for over 30 years and I would not even consider installing an HVAC system in my own home without these three units.