Three Air Conditioning Systems

I have always thought that homes in the Southwest should have three air conditioning systems.

1. Attic or House Exhaust
2. Evaporative Cooling
3. Central (refrigerant) Cooling Systems

I pick the Southwest USA because of the low humidity and extreme high summer temperatures. This is where I have lived for over 30 years. In such climates evaporative coolers work their best in comparison to the Southeast part of the United States. In some areas after sunset the outside air temperature does begin to drop considerably so house or attic exhaust fans are economically efficient to exchange the cool outside air for the hot inside air.

If your house is empty all day absorbing and retaining heat but the evening outside air is cooler, then let’s find a way to exchange the air.

Because hot air rises consider an Attic Exhaust Fan drawing cool air through various attic vent openings, but specifically exhausting to the outside. These can be simply installed and some operate with very little energy consumption.

Now then, let’s get the cool outside air into the living space. Evaporative coolers, sometimes called swamp coolers, force outside air indoors via a water soaked filter. When regularly maintained these are affordable and last for years. The incoming air needs to flow through the living space back to the outdoors. By opening windows slightly in various rooms the incoming air flow from the evaporative cooler will seek the path of least resistance, thus the air flow can be directed to rooms needing most cooling first.

If it is still necessary the Central (refrigerant) Cooling System can now operate within a home that the inside air temperature should have lowered by the other two systems. The Evaporative Cooling system should be turned off and windows and doors closed so the Central (refrigerant) Cooling Recirculation System can work as designed without the initial burden of retained heat within the home.

Know that in terms of operating noise, a properly installed Central Cooling System should operate quietly without notice, whereas evaporative coolers have a defined presence of sound and draftiness.

The question that begs to be answered is, after purchasing an exhaust fan, an evaporative cooler and observing the shorter operation time of central cooling system, what is the net cost?