Indoor Air Quality Heating-Air-Conditioning-Jeffersonville-In-Louisville-Ky
Indoor Air Quality
Beware the hype! Indoor air quality (IAQ) is a really hot topic in the heating & air industry, for both negative and positive reasons. The negative side is that many businesses will capitalize on your health and safety fears to sell you accessories that you really do not need. What follows is information which will hopefully help you decide what is and is not appropriate for your home and budget. We feel that a quality filtration system and possibly a humidifier are essential for a good H.V.A.C. system, for health, comfort and efficiency. Your specific circumstances may dictate a need for additional accessories.
INDOOR AIR QUALITY: Air Filtration
CHANGE YOUR FURNACE FILTER!!! That can really not be said too often and is critical to the performance of your system. We ask that question whenever we get a service call and probably half of the time the answer is that it needs changing. The filter sits in the air stream and all of the return air passes through the filter before the blower moves the air across the evaporator coil. If the filter is dirty then the air will not move fast enough, the blower motor will have to strain and the heat transfer process at the coil will not be efficient. A dirty filter will cause a system to operate as badly as being low on refrigerant and will cause the failure of multiple components. The vast majority of homes use a 1” throwaway filter (located in a filter rack on the side of the furnace). Check this filter monthly! If it does not need changing then do not change it, but check it monthly. With regular checking you will learn how often you need to change your filter based upon environmental conditions. For some reason society is trying to move to changing filters every three months. This laziness is not good for anyone except the heating & air service industry. If you are buying one of the 1” pleated filters that claim to be good for three months, then either check them in between changes or stop using them and use a quality monthly filter. If you want to move to a lower maintenance filter, then consider an annual filter. DO NOT USE THE 1” FIBERGLASS FILTERS! These filters do not capture enough particulates and will cause your blower motor and evaporator coil to become clogged. We sell a very good 1” throwaway polyfiber filter for $1.75 each that we (obviously) highly recommend. If you have one of the boxed 3”, 4” or 5” filters, these are good filters but they are not once a year filters, some need to be changed every three months. Once again, check it, if it does not need to be changed then do not change it. The brand that we really like is an Aprilaire SpaceGard filter. There are three different styles but they all use a once a year filter (though some home situations will require changes more or less often). The replacement filters are 13 MERV (MERV is the rating system used for filters, 13 is a good number) and extremely efficient at removing micron-sized particulates, pet dander, mold, fungi, and, pollen spores. These filters are great in virtually every application and ideal for allergy sufferers. Changing the filters on the new models is extremely easy. Aprilaire also makes conversion kits to change their older models to the newer #2210 and #2410, and, to convert the 4” box style filters to the SpaceGard filter. Replacement filters are $42 each. Unrestricted air flow is more critical in cooling season. If you use an annual filter then try and change it in the spring before cooling season.
Electrostatic air cleaners are somewhat common, though we no longer think as highly of them as we once did. Aside from being less efficient than a quality annual filter, repair issues are a major drawback: it is more expensive to repair an electronic air cleaner than to replace it – one of the more common sights in a home with an electronic air cleaner is to see the cartridge removed and a 4” box filter in its place.
Washable filters are not recommended simply because they do not filter the air effectively. Many older systems feature a coconut fiber, plastic like filter that wraps around a cage. You can try replacing that with a polyfiber filter media that you cut to fit (which we have) or upgrading your older furnace and getting a quality filter system at that time.
Many older systems have a metal screen pre-filter that is washable. Be extremely careful with that because replacements are not readily available or inexpensive.
INDOOR AIR QUALITY: Humidity Control (Humidifiers/Steam Humidifiers/Dehumidifiers)
Humidity control is perhaps the most important, overlooked aspect of a comfortable, healthy, efficient system. Most people never make the connection between comfort and humidity levels, but it is critical: if there is too much or too little humidity in the air in your home then you will either always be too hot or too cold. 35% is the recommended humidity level. Getting it right enables you to raise or lower the thermostat setting and save a great deal of money. Additionally, there are a host of health related humidity issues, from dry lips to nose bleeds to the ability of dust mites to survive (they cannot survive when humidity is below 50%, no dust mites in Arizona!). That being said, the solutions are not always as simple and not always inexpensive.
Adding humidity (usually needed in the dry winter months) is the simplest, cheapest thing to accomplish. It can be done as easily as adding potted plants that you water, getting a couple of goldfish bowls or setting out a pan of water. Of course, these solutions require actions on your part and do not give you actual control of the humidity level. Then you have the choice of stand-alone room humidifiers or a whole house humidifier added to your H.V.A.C. system. The stand-alone humidifiers are fine for small, localized solutions. Bear in mind that the inexpensive humidifier you pick up at Home Depot or Lowe’s is not going to work forever and very likely will be irreparable because of cost or availability of replacement parts. They are manufactured to be replaced, not repaired, so do not spend a lot of money for one. (We do not service these units.) A whole house humidifier is your best solution. These units are added to the front of your indoor unit and tied into the duct system. They have a humidifier pad that should be replaced annually. There are three basic types: a bypass humidifier that uses the furnace blower to move the air across the pad (the most common type, $4-600), a powered blower humidifier ($600-750), and, a steam humidifier ($650-800). For homes using a gas furnace for their primary heat source, either of the first two types should be used. If you have a heat pump for your primary heat source, then you should use a steam humidifier. Humidifiers add moisture to the air steam moving through your system. If the air is not warm enough to properly evaporate the moisture then it can become problematic. Another possible problem with trying to control the humidity level is getting the system to run long enough to add the humidity. This is easily solved by running the furnace blower constantly or setting up an automatic humidistat that could bring the blower on when needed. This becomes a problem with the bypass and direct vent styles because the furnace may not be running, the air may not be heated and the moisture may not evaporate properly. A “can’t go wrong” solution is to use a steam humidifier and leave the blower on constantly. A note about the steam humidifiers: they require the water supply to be filtered and there is an annual filter replacement maintenance cost. Finally, supply and demand economics dictate that repair parts for humidifiers are fairly expensive relative to the cost of the humidifier, but repairs are not commonly needed.
Dehumidification is considerably more difficult. An air conditioner is a dehumidifier, so as long as the air conditioner is running then there should not be an excess humidity issue. However, certain areas of the house, like the basement, do not have the same type of conditioning and frequently have much higher humidity levels. There is also the problem of overly insulated/sealed homes where the air conditioner does not need to run very much and thusly cannot remove the humidity. The only real solution for excess humidity is to add a dehumidification system (which is really a self-contained air conditioner). These are fairly expensive.
INDOOR AIR QUALITY: UV Lights
UV (ultraviolet) lights have been around for some time but really got a boost in popularity after the anthrax scares started because the same type of irradiation technology is used. A UV light assembly is a bulb (or bulbs) placed in the return air stream to irradiate the air flow. This type of technology is used to kill germs and bacteria, and, is generally very effective. It is not extremely expensive to install, however there are regular maintenance costs (replacing the bulbs, usually every two years) that can be somewhat pricey. Generally speaking this added level of air treatment is not really needed if you are using a good filter system. This is not to say that there is no segment of the population that would benefit from a UV light system, such as extreme allergy sufferers or persons with compromised immune systems. For such people a UV light system could prove extremely beneficial.
INDOOR AIR QUALITY: Ventilation/Fresh Air Intake Systems
Sick building syndrome emerged in the 80’s when office buildings were constructed with sealed windows and germs migrated through-out the building because there was no fresh air. Now we are constructing homes that are so completely sealed to the outside that the indoor air becomes polluted. Even if you are not dealing with polluted air, per se, there is frequently stale air in these sealed homes, and, there is the issue of exhausting interior air without having a controlled fresh air intake system. A fresh air intake can be as basic as a pipe through the wall connected to the return air duct side, but problems arise because you are constantly bringing in unconditioned air (hot, cold or humid air) and having to constantly condition it which will significantly reduce the efficiency of your system. Using a fresh air intake system enables you to control the inflow of outside air and to pre-condition the air. These systems are, however, somewhat expensive.
INDOOR AIR QUALITY: Duct Cleaning
We do not do duct cleaning ourselves, and, would suggest that you make every effort to hire a reputable company if you choose to have your ductwork cleaned. A couple of thoughts about duct cleaning: The vast majority of homes do not need duct cleaning. There are two parts to your ductwork, the supply air side which blows air out of the registers and the return air side which sucks air back through your furnace filter. The supply air side blows air so there is no reason to need to have it cleaned under normal circumstances. The return air side can develop build-up in the ductwork over many years, but if you are maintaining a good filter system, then nothing from that side will migrate through the filter. These comments refer to normal circumstances. Of course, if you have had a fire or flood or mold issue, then duct cleaning would not only be helpful but essential to your health. Finally, do not be misled by low price claims. Having your ductwork cleaned properly will cost several hundred dollars. Make certain that you are using a reputable company, perhaps by checking them out with the Better Business Bureau.
INDOOR AIR QUALITY: Other
There are certainly other considerations: smoke detectors (a real no-brainer, do not forget to change your batteries annually), radon testing (maybe useful in a small percentage of homes, but we do not do this), carbon monoxide detectors (a useful safety accessory though did you realize that there is enough carbon monoxide outside your home to set off a detector? and the detectors do require a regular service call for testing), and testing for bacteria (we do not do this, do not recommend it in 99.9% of situations and strongly caution you to beware of scams – there is bacteria everywhere, just because someone swabs your tabletop and shows you bacteria does not mean that you have a health and safety concern),