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Types of Filters Available
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Types of Filters Available

Various types of filters available are,

Filtering your air is much better for your lungs, we can help with that.

  • Standard (panel/fiberglass) Filters - are disposable fiberglass, washable metal mesh or foam type that are installed in series with the furnace. These types of filters catch and trap only larger visible particles of dust and dirt and should be cleaned or replaced monthly. Disposable filters are still the most common types in use. However, this has changed since most Manufacturers no longer supply a basic air filter and as IAQ awareness takes hold, the basic filter is no longer acceptable. Rated according to the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE), standard filters rate 3-5% efficient or MERV 1-4.
  • Media (pleated) Filters - are made up of higher efficient paper, arranged in pleats within a frame and installed in series with the furnace. Both straining and impaction clean the air. The proper media type and size eliminates the need for monthly cleaning. Changing the filter is recommended once a year. One drawback that does occur is that often a larger capacity blower has to be installed on retrofit applications due to the increased resistance to airflow. These filters rate between 25-35%, MERV 5-12, much better than the standard filter. Today this should be the base line filter on all systems!
  • Self-Charging (static electricity) Filters - operate on static electricity. These filters are installed in series with the furnace. As air is moved through the filter an electrical charge is created which attracts particulate. Self-charging filters are not much more efficient than the standard panel ones 10-15% MERV 1-4, because their efficiency drops as humidity and/or airflow increases.
  • Charged Media (dielectric) Filters - are made from a dielectric material (normally non-conductive fibrous glass or cellulose) stretched across a frame and installed in series with the furnace. When a high DC voltage is applied to the dielectric, an electric field is produced. The disadvantage is that the electromagnetic field is not very strong and it's very questionable about performance and actual efficiencies.
  • Turbulent Flow Precipitators (TFP) Filters - these are revolutionary whole house air cleaners designed to offer the kind of performance needed to maintain excellent indoor air quality. They are connected in parallel with the furnace and have their own blower assembly. The TFP filtration process is based on the Dullien principle. During a distinguished career researching methods of pollution control, Dr. Dullien made many discoveries concerning the behaviour of airborne particles. He observed that when particle-laden air is forced through a narrow airway, the particles are repeatedly flung against the internal walls. If the walls are smooth, the particles bounce off and re-enter the air stream. He developed a way of harnessing this natural phenomenon to achieve a high rate of removal of particles from air streams. This new technology is called "Turbulent Flow Precipitation" (TFP). In these air cleaners, the walls of the internal airway through which dirty air passes are made of a pleated fabric that traps particles as they are flung out of the air stream. The result is a MERV 5-8) with no negative effect on airflow through the furnace.
  • Electronic Air Filters - are connected in series with the furnace. Made up of ionizing and collector sections, dirty air particles pass between the ionizing wires that are connected to a high voltage power supply. Potentials from 8,000-10,000 volts strip electrons from the particles, leaving them with a positive charge. These particles pass through into the collector section where they are repelled onto the oppositely charged collector plates. This is by far the most economical way in which to trap airborne particulate. Electronic air filters must be cleaned (washed) every three weeks or once a month. The cost to operate is less than that of a 40-watt light bulb. Efficiency of these filters is 93-95%, MERV 13-16. These air cleaners are very efficient at removing the small particulate down to .03 microns (1 micron = 1/25,000 inch). These are the small microscopic particles that do not get filtered out using conventional air filters and are the major irritant for people suffering from respiratory ailments.
  • High Efficiency Particulate Accumulator (HEPA) Filters - physicians and health officials agree that for severe respiratory problems the 99.97%, MERV 17-20 HEPA by-pass filter combined with an electronic air cleaner is the best combination available. First developed for the nuclear power industry and their long time use in hospitals, clean rooms and laboratories that demand the "clean air" environment make these filters the Cadillac choice. Issues with high-efficiency air filters are; many filters have too high-pressure drops creating a restriction to airflow resulting in increased energy use; many times this required a larger motor resulting again in higher energy use. The HEPA by-pass filter solves these problems while offering the highest removal rate at the smallest particulate size with its parallel method of connection. Many HEPA filter Manufacturer's also make use of two and even three-stage filters. Typically the first stage is a carbon pre-filter, the second-stage is typically a volatile organic compound (VOC) filter and finally the HEPA.



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1567 Logan Avenue
Winnipeg, Manitoba
R3E 1S5
T. 204-775-7744
T. 204-772-5799
F. 204-774-8557


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