How many Envirofans are necessary for peak performance?
Use approximately one 56 inch (or 60 inch) curved tip Envirofan for each 2000 square feet of floor space to destratify heat in buildings with ceilings from 12 feet to 40 feet. For installations with ceilings above 40 feet, use straight tipped blades (reversing type fans).
Straight or curved tipped blades?
Curved tip blades are recommended for mounting heights below 30 feet, and straight tipped blades are recommended for mounting heights above 30 feet. The curved tip blades spread the air over a larger floor area, and the straight tipped blades drive the air down towards the floor.
How many rows of Envirofans should be used?
In a building with a steeply pitched roof, only one row of fans will be necessary, even if the room is over 50 feet wide, as all of the stratified heat goes directly to the peak. In this case, space the fans on 40 foot centers to move the additionally required CFM.
Where should the Envirofans be placed?
Break the building or room up into grids, approximately 35 feet to 50 feet per square, and place one Envirofan near the middle of each grid. Do not place the fans more than 50 feet apart and expect peak performance. If the room is more than 50 feet wide, it is recommended to use two rows of Envirofans.
What type of controls should be used?
Northwest has a full line of controls that will control from one to twelve fans. Our fans require the use of speed controls compatible with PSC motors. In low ceiling, or people-oriented areas (classrooms, offices, stores, churches, etc.) use individual controls. In high ceiling areas (gymnasiums, warehouses, manufacturing areas) use multiple fan controls.
When are transformer controls necessary?
Transformer controls are recommended for any low noise application (churches, theatres, school rooms, lecture halls, etc.) to eliminate any hertz hum which may be audible at low speeds..
What speed should the Envirofans be operated?
Fans should be run at the highest speed that does not cause a draft on the people below. This can be achieved best with the use of an infinite speed control.
How often should the Envirofans be operated?
Fans should be operated full time, 24 hours, 7 days, for the full heating and cooling seasons. The fans will save energy and typically cost just 5 cents per day to operate.
What are the typical savings from Envirofans?
Typical savings, regardless of climate, temperature set point, type of fuel, insulation, etc., is 20-30% of the energy used for heating the area covered by fans.