Ventilation Buying Guide
In any kitchen, the selection of the ventilation equipment is just as important as the selection of the cooking equipment.
How is good cooking ventilation achieved?
A ventilation system consists of three components. All three of these components must work together in unison to provide proper ventilation. Any deficiency in one of these three areas may result in the range hood not performing to its full potential.
The three components are:
- Hood Canopy
- Blower System
- Ducting
Before proceeding to the selection of the correct ventilation system, the type of cooking equipment must be determined. The hood canopy, blower system, and ducting should be designed to handle the heat output of the cooking equipment, measured in watts for electric cooking equipment, and btus for gas cooking equipment.
Hood Canopy:
To properly size a hood canopy, four dimensions must be considered:
Diagram 1
Holding capacity: Hoods do not pull or draw, they only collect. Holding capacity is needed to collect cooking vapors so the blower units can exhaust them to the outside. For standard cooking equipment, under cabinet hoods are appropriate choices. For professional style cooking equipment or barbeque grills, wall mount hoods should be used.
Diagram 2
Overlap: Whenever possible, the hood should overlap the cooking equipment by three inches on each side. On island hoods, this recommendation should be considered mandatory.
Diagram 3
Projection: The hood should project out to the front edge of the front burners in order to properly capture cooking vapors.
Diagram 4
Mounting Height: The hood should be hung at the recommended mounting height to allow for appropriate capture of cooking vapors. Each category of range hood that Vent-A-Hood®® manufactures has a recommended mounting height. Hanging a hood higher than recommended may result in the hood being less efficient at capturing cooking vapors.
Blower System - How much CFM do you need?
B100 Single Blower (300 CFM)
The B100 Single Blower (300 CFM) is appropriate for under cabinet or wall mount hoods for standard electric cooking equipment.
B200 Dual Blower (600 CFM)
The B200 Dual Blower (600 CFM) is appropriate for under cabinet or wall mount hoods for standard cooking equipment, gas or electric, and professional style ranges. Additional blowers may be added if needed.
T200 Island Dual Blower (600 CFM)
The T200 Island Dual Blower (600 CFM) is appropriate for island hoods for standard cooking equipment, gas or electric, and professional style ranges. Additional blowers may be added if required.
T400 Cluster Island Blower (1200 CFM)
The T400 Cluster Island Blower (1200 CFM) is appropriate for island hoods for larger professional style ranges. Additional blowers may be added if required.
Ducting:
NEVER restrict the duct size. The single blower unit (B100) requires 6" round duct or equivalent (28 square inches), and the dual blower unit (B200) requires 8" round duct or equivalent (50 square inches). When combining multiple duct runs together, the square inch area must reflect the total square inch area of the ducts being combined. The proper method of combining two ducts is shown below.
Do not use flexible or corrugated duct. This type of duct will restrict air flow and reduce performance. Only use smooth galvanized metal duct.
Make the duct run as short and as straight as possible with as few turns as possible. Avoid sharp angled turns. Instead, use smooth gradual turns such as adjustable elbows or 45 degree angled turns. Air must not be restricted at the end of duct run. Do not use screen wire or spring loaded doors on wall louvers or roof jacks. Do not terminate vent into an attic or chimney. The hood must be ducted to the outdoors.
