Selecting a System
Zoned or Central?
The first task is to determine the number of fans that you will need based on your lifestyle and layout.
Central (single-fan) system
A centrally installed system is one large fan installed in the top and central location in the home. This is usually the center of a single story, or at the top of the stairs in a two-story home. A single QuietCool system is strong enough to nicely ventilate an average home, and is a good choice for smaller households or homeowners on a budget.
Zoned (Multi-fan) system
A multi-fan zoned system gives the homeowner maximum control over their ventilation and cooling needs. When sizing a zoned system, the combined CFM of all zoned units (not each individual fan) needs to match or exceed the total CFM requirements. All zoned fans can be turned on simultaneously when the entire home needs to be cooled, but a zoned system also allows individual area control. For example, if you’re going to bed at night, rather then running the central system, turn on the bedroom unit only.
While a square shaped living space usually has only a single fan, L-shaped or large rooms with multiple living areas can benefit from multiple smaller fans.
To determine the size of the fans you will need, calculate the square footage of your rooms and multiply by the height of the ceiling. This is the volume of your home. Hawaii systems are sized for a complete air exchange of that volume in 2-3 minutes or less.
For Hawaii homes we recommend:
- 1500 CFM (QC/ES) Fans for a standard bedroom
- 2250 CFM Fans for a master bedroom
- 3100 CFM Fans for a living space of 600-900 square feet
- 4700 CFM Fans for a whole home area of 900-1600 square feet
- 5400 CFM Fans for a whole home area of 1600-2400 square feet
Each fan needs 1 square foot of net free venting per 750 CFM. (A 4500 CFM system would need 6 square feet of venting). The attic venting you choose will be specific to your home and roof type. Homeowners can increase their venting by adding gable, ridge, roof top or soffit vents.
Article courtesy of IslandCooling.com