Crystal Air P.O. Box 1501 Weaverville, CA 96093                                   1-530-623-1000                                                  California State License Board #762833

Air Quality

As we build homes with better insulation and tighter seals against leakage (known as fenestration) we must take measures in light of these improvements in efficiency to ensure the quality of the air inside a building (known as an "envelope")

When we keep the warm or cool air in a building from passing between the inside enviroment and the outdoor enviroment, we can begin to experience some unwanted and even unhealthy conditions. Odors, pet dander and even toxic gasses such as carbon dioxide, formaldehyde and volatile organic compounds (VOC's) from cleaners and chemicals can become problematic..

So, we have become very efficient at sealing a building to keep in the temperature conditions that we desire but, now we are forced to actualy bring air in from the outside and/or filter it in order to be safe. It is an apparent irony that our efforts to be energy concious might yield a health risk. Fortunately, there are solutions to remedy this dual purpose and need.

The answer to this call is to provide sufficient filtration to a building envelope as part of it's heating and cooling system (central air system and ducts) and, allow for some exchange of fresh air between outdoors and indoors without loosing the heating or cooling inside that we worked so hard to achieve.

Before you read on, we recomend that you take some time to read up on the current California Code Requirements that impact heating, cooling, and ventilation on our page for current codes here. Understanding them better will help you to have a better scope on what has been established as minimum criteria for indoor health safety.

Respicare Return Register Filter

This unit comes in various sizes to match your return register grill and is equiped with an electronic unit that drives a small metal insert that efficiently collects particles to sizes commensurate with pet dander, many molds spores, and pollen. It does not perform to the level of providing the best filtration for very small particles such as respirable dust and bacteria. Installation is simple requiring only some simple wiring from the filter to a low voltage electrical source on your primary air unit for the enclosure. Installation and equpment typically run from $400-$500 and the unit needs to have the filter media cleaned and replaced monthly for best results. Replacement filter media runs about the same as conventional fiber media filters. We generally recomend purchasing a years supply upon installation as they are not available through local retail outlets.  This small easy to install filter system is great for people with allergies and to help cut down on indoor odor build up.

Aprilaire 5000

This is a flagship line filter unit and the  choice for those that desire the best air quality indoors, suffer from asthma or have health concerns related to airborn bacteria and molds. This unit is installed directly onto your air blower unit and has a great deal more muscle and capacity to filter large volumes of air and remove up to 94% of particles down to the size of airborn bacteria. Typical installations and equipment  for this unit will run from $1200-$1400. The unit requires only once a year cleaning and replacement of the filter. Filters typically run $60

Included is a user friendly control panel to monitor and adjust the performance of the unit

IMPORTANT NOTE: If you suspect that your building itself has an issue with the presence of mold due to indemic dampness or molds from any source other than natural airborn spores as the result of infiltration from outdoor air, seek a professional technician qualified  in irradicating the source of the mold and it's causes. Mold growing inside the house poses a serious health risk and filtration alone will not rectify a larger issue.


In this context, we are speaking primarily about aspects of filtering the air in the home to a greater degree than what can be provide by the typical "unit filter" that we are all familiar with and is installed in a central air register grill. This type of filter is primarily for the purpose of filtering particles in order to mechanically protect your heating or cooling system and provides little in terms of screening for odors, dander, molds and allergens. For information on "unit filters, what to choose and how often to change, please visit the Crystal Air page for Maintenance here.

"What's best for me?"

The level of filtration for you truly depends on your desires and health concerns. Crystal Air has access to any filtration unit that you may want but, we find that customer's needs and budget are satisfied between one of two units that most of our customers select from. If you are generally looking to reduce odors, improve the freshness of indoor air or screen for pet dander, we recommend the Respicaire "in grill" unit below. If you have more serious health concerns for filtering bacteria, molds or suffer from an asthamatic condition then, we invite you to read more on the Aprilaire 5000 unit as an addition to your central air system.


Designing and installing a system for the exchange of fresh air to and from a building enclosure can be a simple task if we are not concerned with the potential loss of heating or cooling that may result.  This type of ventilation is something that Crystal Air does provide services for but, we prefer to educate and provide you with a better solution.

Fresh Air Without Loosing Heating or Cooling

As stated previously, we have our work cut out for ourselves in that we have reduced the leakage of air from and into a building  through better materials and techniques for insulating but, need to allow for some exchange of fresh air for the sake of health. Technology has provided us with what is known as a "Heat Recovery Ventilator" or HRV.

This unit installed into a building resolves our dual purposes by introducing fresh air exchange in a manner that recoups the inside air temperature that we have worked so hard to preserve. Many models are available but, our favorite and most recomended unit is produce by Fantech.

Current Codes for Ventilation

Today's current mandates for building enclosures have raised the bar on what energy efficiencies a home must achieve as well as requirements for fresh air ventilation. Installing a heat recovery type ventilator will aid us in meeting both requirement criteria.

Heating, Cooling, GeoThermal, Hot Water &
Air Filtration Experts


Solutions for Serious Conditions

For consumers with serious health conditions requiring further eradication of bacteria and/or air born viruses, Crystal Air offers installation of Ultraviolet Light sterilizers to be used in conjuction with physical filtration units and attached to the central air system.

Air Quality In the News