Room Air Purifier in Central AC Home

[c210flyer]

I own a 4000 sq. feet two stories home with a two zone central AC system. My wife suffers from asthma and allergies and believes that the air quality in the house could be improved by purchasing a room air purifier. She wants to use the purifier in the kitchen which is a relatively open room.

While I have not calculated the ACH for my Central AC, it seems to me that the room air purifier would be attempting to purify a very large volume of air with the associated filter changes and the expense that goes along with it.

I am pretty judicious at replacing the central AC filters on a regular basis but she is still complaining.

Do you think that a room air purifier could make a measurable impact on the air quality of a relatively small area given the conditions I described or would it be a waste of money?

Thanks for your help.

Steve

[teddy bear]

Better indoor air quality
A minimum of a Merv 11 air filter on the air handler is a start. 24/7 air flow through the filter. A fresh air change in 4-5 hours when occupied, or 24/7.
Maintain 47%-50% RH through the warm months, +35% during the dry months for comfort.
Mold, dust mites, pollen, and indoor air pollutants are the main problems.
Mold in basements/crawlspaces and a/c ducts are common problems because of dampness in these spaces.
In green grass climates, most homes need supplemental dehumidification to maintain <50%RH during low sensible cooling loads and high outdoor dew points, +55%RH. The other source of moisture is from the occupants. You may need 5-6 lbs. of dehumidification per hour. Also the whole house dehumidifiers work well to provide filtered fresh air in addition to the supplemental dehumidification. Mold and dust mites are unable to reproduce in the <50%RH conditions. It takes months for the mold/dust mite allergen to lose its effect on allergic occupants.
Small air filters are ineffective in the big picture. Ok for an isolated area that has fresh air and is dry and clean
Keep us posted.
Regards Teddy Bear