Why Humidity Matters when Cooling


Why is fresh air humidity control important?

The Eco Breeze has a dynamic control system that constantly monitors changes in both indoor and outdoor humidity to maximize the use of fresh air cooling whenever it is available.  It also makes sure the humid air stays outside and avoids bringing uncomfortable sultry air into the home.    Why do you care?  Humidity plays an important role in your comfort and in the energy required to run air conditioners.  Low humidity increases evaporation which makes us more comfortable.    High humidity causes that muggy feeling and requires lower temperatures to be comfortable.   Air conditioners are designed to provide two types of cooling to increase our comfort.  They reduce the indoor humidity (latent cooling) and lower the temperature (sensible cooling).   On many days opening windows can actually increase indoor humidity, which will decrease comfort.  In addition when the air conditioner is switched on it will need to work harder to remove the moisture raising air conditioning utility bills.  Eco Breeze will only bring in fresh air cooling when the outdoor humidity will not decrease indoor comfort.  It is important that this is a dynamic or continuous monitoring since humidity is constantly changing.  Inside of our homes, cooking, showers and just more people will raise the humidity level.  Outdoors weather fronts and rain storms can raise humidity just as sunny days and fronts can lower humidity levels.   Eco Breeze continuously measures both the indoor and outdoor humidity levels and will only use fresh air cooling when the outdoor humidity is lower than the indoor humidity.   Measuring and controlling for humidity insures that the humid air will stay outdoors!

How does Humidity affect comfort?

Humans are sensitive to humid air because the human body uses evaporative cooling as the primary mechanism to regulate temperature. Under humid conditions, the rate at which perspiration evaporates on the skin is lower than it would be under arid conditions. Because humans perceive the rate of heat transfer from the body rather than temperature itself, we feel warmer when the relative humidity is high than when it is low.  Another way to say this is when the relative humidity is high, the evaporation rate is reduced, so heat is removed from the body at a lower rate, causing it to retain more heat than it would in dry air.  For example, if the air temperature is 80 °F and the relative humidity is 45% percent, then the air temperature feels like 80 °F.  If the relative humidity rises to 60% the air temperature feels 2 degrees warmer or 82 oF.  At 80% relative humidity the temperature feels 4 oF warmer or like it is 84 oF.  Eco Breeze is designed so only lower humidity air will be used for cooling which will maximize your comfort.

How does Humidity affect air conditioner energy?

Air conditioners are designed to provide two types of cooling to increase our comfort.  They reduce the indoor humidity (latent cooling) and lower the temperature (sensible cooling).   Both types of cooling take energy.  At 80 oF it takes as approximately the same amount of energy to reduce the relative humidity by 20% as it does to reduce the temperature by 5 oF.   Adding humid outdoor air to the house will make the air conditioner work harder and can double the energy consumption as the humidity is removed from the air.  Eco Breeze will only operate when the outdoor humidity level is lower than inside humidity, saving energy when the home is being cooled by the air conditioner.