Swamp Cooler Feature Guide
Swamp coolers are sized by cubic feet per minute (CFM), which refers to the amount of air the cooler can circulate. Most models will have CFM ratings ranging from 3,000 to 25,000 CFM. To effectively cool down a room, you want to be sure that you choose one with sufficient airflow.
A simple formula is all that's required to determine the CFM rating for a properly-sized cooler. Take the cubic feet of the space you wish to cool and divide that number by two. For example, if have a 1,800 square foot home with 9 foot high ceilings, you would calculate your CFM requirements like so:
1,800 x 9 = 16,200 cubic feet
16,200 / 2 = 8,100
CFM Requirement: 8,100 CFM
Unlike portable air conditioners which require specific BTU ranges in order for the unit to cool properly, there's no harm in purchasing a swamp cooler that slightly exceeds your cooling needs.
|Direct vs. Indirect Systems|
There are two different types of evaporative coolers: direct and indirect.
In a direct swamp cooler, a blower forces air through a water soaked-pad, where it is then cooled, filtered, and humidified. This air is blown directly into the building. Popular and inexpensive, and most portable and industrial swamp coolers use direct systems.
Indirect swamp coolers have a secondary heat exchanger which prevents humidity from being added to the air. Because these systems do not add moisture to the air supplied to the home, this lowers their cooling capacity.
|Water Consumption and Tank Capacity|
Because they require water to keep the cooling pads wet, a swamp cooler can use anywhere from 3 to 15 gallons of water per day, depending on the size of the swamp cooler and the ambient temperature.
If you live in an area where there's a drought, pay close attention to the amount of water the swamp cooler consumes, as this will affect your operation costs.
The size of the water tank will determine how often it needs to be refilled. Some models have hose hook-ups that allow for continuous refilling.
|Ice Tanks||In addition to water tanks, some models include ice trays or even ice packs for additional cooling capabilities.|
|Variable Speed Options||Look for units with at least two speeds and a fan-only option. Variable speeds allow you to control the cooling efficiency of the unit. The fan-only option turns off the water pump so the air isn't cooled or humidified - allowing you to use the cooler as a whole-house fan.|
|Efficient Fan Motors||Evaporative air coolers use a fraction of the electricity of air conditioners (almost one-third less). Portable units usually only cost pennies a day to run and use standard household outlets. Nevertheless the fan and pump still use electricity, and so it makes sense to find a model that is the most energy efficient.|
The moist pads within a swamp cooler also double as air filters, cleaning dust, dirt, odors and other pollutants from the air.
Some also include built-in air purifiers, complete with HEPA filters, ionizers, and activated carbon - something to consider if you're an asthma or allergy sufferer, or have pets in the home.
Large evaporative coolers can be somewhat complex to install, particularly if the model is designed to cool the air throughout an entire home. The unit will need to be mounted on an external wall or roof and connected to the interior ductwork.
Installing a portable evaporative cooler is much easier. Open a door or window to allow plenty of air circulation, plug it in, and switch it on. Also, as long as the water tanks are constantly filled to capacity, they will work to cool a room or area to the desired temperature.