CO2 Sensors for Demand-Controlled Ventilation

Demand-controlled ventilation, or DCV, adjusts a building's fresh air rate to match occupancy instead of running at a fixed rate all day. A CO2 sensor tells the BMS to bring in more outside air as CO2 rises with the number of people, and less when the space is empty, cutting the energy needed to heat, cool and move that air.

It depends on how much occupancy varies through the day. Spaces that are often partly empty, such as meeting rooms, schools and auditoriums, save the most, because ventilation only runs at full rate when people are actually there. We can help estimate the saving for your building.

Many designs use a setpoint of around 800 to 1,000 ppm above outdoor level to trigger extra ventilation, but the right value depends on the ventilation standard that applies to your project and the space's occupancy pattern. Confirm the setpoint with your HVAC consultant.

Use a room sensor, such as the RT-CO2 or RTX-CO2, where each space needs its own ventilation control, for example a meeting room that fills and empties through the day. Use a duct sensor, such as the HDK, where one air handling unit serves an open-plan area and an average reading is enough.

Produal CO2 sensors connect to BMS controllers through configurable outputs, so most systems can read them. Tell us your BMS make and the input it expects, and we'll confirm the right output option for your project.