Timer control and demand control do different things. Timer control defines when ventilation runs. Demand control adjusts how much ventilation is needed right now.
What does timer control do?
A timer schedule starts, stops, or changes ventilation output at preset times. You can define separate operating periods for full and reduced output, and times when ventilation is off. A well-set schedule prevents ventilation from running unnecessarily at night, for example.
Timer control does not know what is happening in the kitchen and cannot adapt output to real need. It follows a preset pattern regardless of whether activity in the kitchen is low or high.
What does demand control do?
Demand control adjusts air volume based on sensor data according to the kitchen’s actual situation. When load increases, ventilation is increased. When load decreases, air volume is reduced.
Can timer control deliver energy savings?
If ventilation runs clearly longer than needed, adjusting the timer schedule can save energy. With a timer schedule, building maintenance must still estimate in advance when ventilation is needed and at what output. Demand control removes that guesswork: ventilation adjusts automatically to the kitchen’s real need.
How big can the difference be?
At Turun Teknologiakiinteistöt’s Kupittaa Pavilion, kitchen ventilation was controlled by a timer schedule before FlowHero. After FlowHero was commissioned, exhaust air flow was reduced by 49 percent compared with timer control without worsening indoor conditions. Annual energy savings were calculated at 69.5 MWh and cost savings at €5,539.