3 Generations of Happy Neighbors

Schedule Maintenance Request a Quote

Indoor Air Quality

Indoor Air Quality, or IAQ for short, has become a growing concern for the heating and air conditioning industry as well as with the general public. As we have become more energy conscious and building methods have changed towards tightening houses through higher insulating standards we have created new health concerns.

Newer homes don’t “breathe”; that is, newer homes do not have as many fresh air exchanges as older homes. This results in trapping in pollutants and toxins ranging from pollens to off-gases from building materials. Respiratory illnesses have increased dramatically, especially in infants and young children. There are many products available which can increase air quality in the home. Understanding the different products on the market and how they can help is the key to making a wise purchase.

There are three basic areas of concern when we discuss items which cause allergies and asthma: particulate (ex: dust, pollen, pet dander), microbials (ex: bacteria, mold, mildew), and V.O.C.’s or volatile organic compounds (ex: gases from home products). Different products concern themselves with different aspects of the indoor air quality problem; there is no singular product which handles all three areas of concern. Depending upon personal needs, we can best match the correct solution to the problem. If pollens and dust are the problem then we need a good filtration system. If molds and mildews are the concern we turn towards UV light systems and dehumidifiers. Gases and odors are attacked with ozone generating systems.

Air Filtration

Filtration systems can range from very basic to high tech. If a filter only costs 99 cents you might guess what kind of results one can expect. That’s not to say that you must spend $2000 to get a good system either. There are a variety of good systems available ranging from $500 to $1500. Most of the one year media filters are good against dust, pollens, and dander. These filters typically increase in efficiency as they become loaded and are effective against particulate down to 3 microns (a micron is about the size of the point on a fine sewing needle).

Electronic air cleaners such as the Aprilaire 5000 are a step above the media filters. These systems add voltage for attracting very small particulate and work quite similarly to a magnet. Electronic air cleaners are very good against all pollens, small dust, and dander and are up to 98% efficient down to .3 microns.

A step above all of the other filtration devices are the true HEPA air cleaners. HEPA stands for high efficiency particulate arrestant. HEPA air cleaners utilize multiple pre-filters, a charcoal filter, and a high efficiency HEPA rated filter. These units bypass a portion of the air from the hvac system, clean the air, and then send it back to the hvac system. These systems are designed for severe allergy sufferers and for those with other respiratory illnesses.

Microbials, V.O.C.’s and Dehumidification

Mold and mildew within your home can be eradicated in different ways. UV germicidal lamps not only kill mold spores and mildew but also bacteria. A UV lamp is typically installed into the duct system and the airborne spores and bacteria are killed as they pass through the light field or kill zone. The more of the house air that passes through the light field the higher the kill ratio.

Ozone is a naturally produced element of the air we breathe. Produced when oxygen is exposed to UV light from the sun or to an electrical charge such as lightning, ozone serves as the earth’s air purifier (our first IAQ product). Ozone can also be artificially produced by man and is used to neutralize gases and V.O.C.’s. Ozone and oxygen are almost the same chemically. Ozone possesses an extra O molecule which is unstable. This extra O molecule wants to break off and latch onto another compound. Finding other gases, the O molecule will chemically break down the new compound making it less volatile or inert.

The Naturesoft air purifier is a product we have been selling because it combines both UV and ozone technologies. I have a number of these in the field including a test unit in our office. The results have been outstanding. Replacement lamp cost is very low compared to other purifiers on the market plus this unit is produced locally so we have continuous product support.

Another way to prevent mold and mildew within your home is to take away what they both need to survive: moisture. Whole house dehumidifiers are designed to keep your home dry enough from spring through fall to prevent mold and mildew from flourishing. The problem with store bought dehumidifiers is that they are not designed to work in cooler temperatures such as your basement where moisture levels are at their highest nor are they designed to deal with large cubic areas. Therma-Stor and Aprilaire both offer a complete line of whole house dehumidifiers to meet every application and every need.


During the winter months our indoor air quality concerns turn toward the dryness of our homes. As temperatures drop outdoors the relative humidity drops indoors. In the heart of the winter we’ve tested humidity levels in our customers’ homes below ten percent. Now that’s awfully dry. Our respiratory system does not like such low humidity levels and we become more susceptible to colds and the flu under these conditions. Our home fixtures such as furniture, cabinetry, and decorative wooden trim will contract under low humidity conditions. Static electricity will be common place throughout the home. Aprilaire offers an assortment of different capacity humidifiers to keep your home from feeling like a desert during the winter.

Making the Right Choice

With all the different IAQ products on the market, choosing the right unit is not always easy. Part of Appel Heating & Air Conditioning’s job as your service company is to research the products available and to choose the ones that we feel will best serve our customers. We also feel that it is imperative for us to educate our customers and hope you’ve found this page informative and useful. Let us know how Appel Heating & Air Conditioning can help you in choosing the right IAQ product for you, your family, and your home.