Ultra Violet Light
Home
Carbon Filters
Capacity of Ultra Violet
How Does it Work
Ultra-Violet Disinfections

Our Partners
Water Purification Kits
Water Treatment Pro
A1 Water Softeners
Reverse Osmosis Filter Systems
Ultraviolet Light

Activated Carbon Filters

Activated carbon filters are generally used to eliminate undesirable odors and tastes, organic compounds and to remove residual chlorine. These filters absorb impurities as they pass through a carbon cartridge. As far as efficiency in terms of removal of contaminants is concerned - these filters do not remove most inorganic chemicals, metals, microorganisms and nitrates, to counter these contaminants from entering your water supply, you should add a UV sterilizer and reverse osmosis filter to your system.

However, carbon filters are very important and efficient in the removal of some potentially hazardous contaminants such as radon gas, many dissolved organic chemicals and tri-halo-methane. In case the water supply has a low level of these contaminants, this filtration system can easily and effectively be used as a whole-house unit. However, cases where the level of these contaminants is persistently high, these filters are not the solution for removal and purification. In these cases, or when contamination cannot be eliminated by usage of carbon filters, it would be safest to choose an alternative water supply as the most cost and health effective system.

When using a carbon filter, it must be remembered that these need to be replaced periodically. With continued usage, as the filter gets saturated with contaminants, it loses its effectiveness and must be replaced. Instead of replacing or delay in replacement can result in contaminants to be flushed into the drinking water. This can be unhealthy and must be avoided. All these filters have a rated life beyond which they should not be used. Therefore, it is important that before purchasing the unit, all information such as can the filter can be replaced, the frequency of replacement, where replacement filters may be purchased and how much they cost should be obtained from the dealer. This factor may influence your decision on the model and type of system being purchased.

A property of the material used in an activated carbon filter that must be borne in mind is that it provides a growth surface for certain bacteria. Therefore, if the filter has not been used for five or more days, you must clean the surface. This can be achieved simply by running chlorinated water through the filter for at least 30 seconds before use.

Because carbon filtering devices use carbon cartridges that have a porous surface, it allows the cartridge to absorb a variety of substances, including THMs, odors and disagreeable tastes. This may not be very agreeable. The effectiveness of a filter depends on the amount of carbon that is in the unit and also on how long the water stays in the unit. As a norm, the longer the water is in contact with the filter medium, the more time the carbon has to remove impurities. Therefore, those filters that are packed with a large volume of charcoal tend to remove more organic material at the beginning of the cartridge life. However, the advantage is that the performance of these high volume filters tends to decrease less rapidly over time than it does for those containers with a small amount of charcoal.

• Faucet-mounted carbon filters attach to a faucet after the aerator is removed.

• There are two basic designs of carbon filters. One uses a by-pass valve that filters only water for cooking and drinking. The second design has no by-pass valve and therefore, it filters all water flowing through the faucet. Additionally there are those that are not permanently attached to a faucet. These models are placed on a counter and have a hose running from the faucet to a charcoal filter.

• Then there are pour-through (portable) filters. These are used effectively to remove contaminants from water on recreational vehicles, on boats or at campsites. However, in this case, you have to make sure that the water started with is suitable for drinking (potable water). Water poured through the filter flows into a container, is collected and consumed. This is the simplest form of all carbon filters, especially if it is the non-powered variety. There also exist models that are powered and operate on a 115-volt current; there are some others that operate on a 12-volt line or battery. The rate of filtration in the units that are powered is much higher when compared to the non-powered filters. Some of those operating on a 12-volt battery can filter up to 1-1/4 gallons (4.7 liters) in two minutes.

• Specialty-type filtering devices such as ice maker and scale filters are placed on the cold water supply line to appliances. Ice maker filters are attached to the cold water line to refrigerators or standard ice makers. Scale filters are connected to the supply line of water heaters or humidifiers.

• A line by-pass filter may be installed in any one of the two locations. The first location is beneath the sink where it is attached to a line leading to a separate faucet at the kitchen sink. The second location is in the water line after it enters the house. When installed in the water line after it enters the house, it also requires installation of a valve in the water line ahead of the filter in order for the water that is drawn from the regular faucet to be shut off.

• A stationary water filter is installed in the cold water line under the sink. All cold water flowing through the pipe to the kitchen is thus filtered.