HVAC control - Regulate kitchen exhaust hood speed according to temperature

“My restaurant’s exhaust hood is always running at full speed, even when my cooking equipment isn’t being used. I’d like to fi nd a way to reduce the amount of energy wasted and lower my utility bills.”

The solution consists in using variable speed drives (VSD) to adjust exhaust operation to the amount of activity in the kitchen.

Fan speed is controlled according to air temperature. A sensor inside the exhaust hood detects air temperature, and an Altivar 12 variable speed drive adjusts the exhaust fan motor speed.
The cooler the air, the slower the fan runs, down to a minimum ventilation level. The exhaust hood is automatically turned up or down to meet actual needs, resulting in substantial savings.
An optical smoke sensor can be added to boost the system’s regulation capabilities. This configuration requires an additional control system.

> Energy savings of 20% to 50%, depending on use: maximum exhaust hood operation is usually limited to just a few hours a day

> Fast ROI, usually within 18 to 24 months

> Quieter operation

• Lowering fan speed by 20% reduces noise by 20%
• Reducing speed by half virtually eliminates noise

> Lower maintenance costs

+ Design

• Simple and economical: the VSD picks up the signal directly from the temperature sensor
• Reduced maintenance: the VSD can be mounted right on the fan, eliminating maintenance-intensive gearboxes
• Easy design and upgrades

+ Installation

• Complies with international standards
• Integrated EMC filter
• Simple, beltless system
• Easy installation thanks to plug-and play design