An Air Conditioner or Whole House Fan, What's Best?

As summer is quickly approaching, let's explore two ways to keep your home comfortable – air conditioning units and whole house fans.

Both have their benefits and limitations, so let's take a look to see what might work best for your home.



Air Conditioners

A central air conditioning system is the ultimate workhorse of cool air – you select a temperature and the AC unit continuously works to keep your home's indoor air consistently at that temperature. 

An air conditioner takes the existing air inside your home and cycles it through a cooling system, cooling it slightly each time in passes through the unit. Air conditioners can be used any time of the day, and are independent of the outside air temperature (and humidity!).


  1. Air Quality – AC units circulate and help filter the air within your home, removing common allergens.
  2. Lowers Indoor Humidity – helping to decrease any growth of dust mites and mold.
  3. Consistent Indoor Environment – used anytime day or night, the indoor temperature remains consistent despite any changes in the outside weather conditions.
  4. Comfort Controlled – thermostats allow you to select a temperature that best suits you.
  5. Home Security – AC units to not require an opened window or door to operate, allowing you to keep loved ones and valuables better protected.
  6. Home Electronics – A controlled climate prevents electronic devices from overheating during the heat of the day.
  7. Environment – New AC units are environmentally friendly compared to units of the past.  While they do use refrigerant, the refrigerant is a closed system that is never intended to vent or leak.  Properly maintained, the refrigerant should never have to be added to.  
Consider this: You can also use your AC’s duct system much like a whole house fan; simply turn on the fan switch when you want to circulate air throughout your home.


A Whole House Fan

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First, we aren't talking about attic fans, which only circulate the air in your attic. Whole house fans ventilate your home by circulating air throughout the whole house, pulling the hotter air out of your living space and drawing in cooler, fresh outside air through open windows. This system works well when the outside temperature is cooler than the temperature inside of your home.

While there are many advantages, whole house fans do not provide the same level of cooling as a full AC system. That being said, let's look at a few of the benefits.


  1. Cost of Operation – far less expensive than an air conditioner, averaging 90% less energy use.
  2. Ventilation – continuously replaces stale indoor air, which can be polluted by allergens, pet dander, smoke, etc., with outdoor air. Typically a whole house fan will provide 30-60 air changes within your home each hour. Note, however, that a whole house fan does not filter the outdoor air.
  3. Environment – more environmentally friendly as an energy saving option that does not use refrigerant to cool the ambient air.


What's Best?

There's no "best" answer, as it really does depend on what level of comfort you would like in your home while taking into account the costs and efficiency associated with both options.

For most of us in Flagstaff and northern Arizona, an air conditioner will provide the most comfort during the more hot and humid monsoon season – those times when a whole house fan simply cannot cool the home effectively. A whole house fan can, though, create a comfortable environment through our more moderate seasons.

Consider both.  There is a practical value, as well, in having both. By running your whole house fan during the nighttime's cooler temperatures, you'll cool your home considerably, and well into the following day. As the day heats up, run your AC. This can keep your cooling costs and energy use low while keeping your home comfortable throughout the day and night.



Contact us to help you decide on the level of comfort you'd like when you seek relief from warm temperatures.