What Happens When The Total ESP Is Exceeded?
How Do Filters Play A Part?
As A Homeowner, What Can You Do?
Do you or your loved ones suffer from allergies? Would you like to reduce home heating and air conditioning costs? Simply upgrading the air filter in your heating or cooling system can make a huge difference in both of these areas.
– According to the U.S. Environmental Protection Agency indoor air is two to five times more polluted than outdoor air. That is a crazy bit of information.
– The average person breathes in about 32,000 pts. (18,185 litres) of air each day. Those 32,000 pints contain approximately 1,120,000,000 particles of dust. Most of these particles are 3 microns or smaller in size and you usually don't even see them.
There are many things that effect indoor air quality and efficient air conditioner filters and furnace filters are your primary defense against these indoor air quality problems.
Inefficient air filters are primarily of the fiberglass panel type and many of the pleated panel filters are not very efficient either. These filters do nothing to help with allergies or protect your heating or cooling equipment.
Air filters that are not very efficient allow too many allergens and dust pass through and return to your home. This results in allergy problems and a lot of dust settling on furniture and appliances throughout your home.
There is another problem that many people are not aware of. The dust that is not caught in the filter also builds up on cooling coils of your air conditioning equipment which in turn cause you to need ac evaporator coil replacement.
One more way that the equipment is robbed of its operating efficiency. As operating efficiency begins to drop off the equipment has to operate longer to reach or maintain its set point. Longer run times results in faster equipment wear and higher operating costs such as furnace vent cleaning.
As air filters become plugged with dust they begin to have a negative impact on air flow through your furnace or air conditioner. As the air flow begins to be reduced the operating efficiency of the equipment is also reduced.
A simple rule of thumb for furnace filters is – Don't Use It If You Can See Through It.
This doesn't mean that you should not be able to see some light through the filter, it means that if you can put your hand on the other site of the filter and see it, then the filter is almost useless for dust control. Guaranteed useless if you have allergies.
Total ESP stands for Total External Static Pressure. This is the highest resistance for which the fan is rated. Manufacturers rate their systems for 0.5″w.g. That is not much considering it includes the downstream ductwork, the return air ductwork, the evaporator coil, and the filter.
When Total ESP is bigger than the fan's rating, the fan will "ride the fan curve," or reduce speed. In commercial buildings, some manufacturers use this principle to modify the output of fan powered variable air volume terminals (the boxes in the ceiling plenum that control the mix of air delivered to an air conditioning zone).
Manufacturers use dampers as an economical means of increasing the downstream static pressure, slowing the fan, and reducing the volume of air. The principle is the same in homes. When the Total ESP is exceeded, the fan slows.
1. There may not be adequate air flow to guarantee enough air is delivered to the end of the longest duct runs. When this happens, those rooms may feel stifling and too hot or cold, even though the temperature may be comfortable elsewhere.
2. The air flow passing over the evaporator coil may be insufficient to guarantee proper dehumidification. If the evaporator coil doesn't fully dehumidify, it and/or the surrounding plenum box can become a breeding ground for bacteria and contaminants.
Filters have a "pressure drop" or amount of resistance. Even the cheap, disposable filters can become a problem if they are not replaced on a regular basis. When dirt collects on the filter, the pressure drop elevates. Even worse than the cheap, disposable filters are the high pressure drop filters, which have pressure drops of 0.35″w.g. pt or higher. People buy these filters to enhance air quality.
The HVAC industry has numerous solutions for the homeowner who wants better filtration than the minimal amount found with a disposable filter, but don't want the comfort/bacteriological problems of a high pressure drop filter. These include HEPA (high efficiency particulate arresting) filters, deep pleated media air filters, and electronic air cleaners.
A newly introduced air filter guarantees to attract pollen like a magnet, due to its dual-panel mulltilayer technology. Paul Honnen, president, PollenTec, Phoenix, noted that the air filters are made from PolllenTec material, which has been tested and certified in a hospital setting and can effectively capture up to 100 percent of airborne pollen spores.
The filters are made utilizing four cross-directional layers. The filter's first two layers capture all airborne pollens and the bulk of other microscopic particles, and the second two layers ensure that remaining particles are trapped. The MERV 8 PolienTec filter captures allergen-size particles as small as 0.3 microns and can be washed and reused.
The PolienTec filter is a 1-inch filter that is available in any size, the unique design of the filter allows for fast and easy cleaning and the company states that PolienTec filters can last for up to five years.