Energy Efficient HVAC Controls Toolkit

Many benefits can be derived from installing controls on your HVAC system. These range from increased workplace comfort, to improved system efficiency, reduced energy costs, and greater knowledge of system performance. In order to use theses controls efficiently, it’s important to note the optimal conditions under which your building should operate.

Controls can also be set to slow down or shut off  HVAC equipment based on set time or occupancy schedules.  This can save a significant amount of energy as the system is only being operated when needed.

Types of Controls

Time clocks can be implemented in multiple independent circuits so that each can have its own operating schedule. This allows for even greater control over specific areas of your HVAC system.

A start/stop optimizer works by assessing the outside air temperature to determine when the HVAC system should start up to ensure comfortable building temperatures by the beginning of the work day. In addition, an optimizer can shift to a nighttime setting to ensure energy isn’t being wasted when the building is unoccupied. This can be a great energy saving tool as opposed to fixed time starting/stopping as it more precisely operates the HVAC system based off actual temperatures, which can vary greatly day to day, and season to season.

Montana commercial energy code requires that automatic start controls be provided for each HVAC system. The controls must be capable of automatically adjusting the daily start time of the HVAC system in order to bring each space to the desired occupied temperature immediately prior to scheduled occupancy. 

Demand Controlled Ventilation is a great way to save energy within your system by providing ventilation only when it’s needed. Air exchange rates can vary greatly depending on building use and occupancy factors. Sensors can be installed that detect CO2 levels and other pollutants, providing information on the ventilation needs of a particular room or building. This information can be utilized to make proper adjustments to ventilation equipment.

A variable speed motor is another energy saver that can be installed on fans and other ventilation equipment. As opposed to just an ‘on’ or ‘off’ setting, a VSM (or motor controlled with a VFD) allows the ventilation system to control air exchange rates more precisely depending on the building’s needs.