Energy Efficiency Standards Regulation Enforcement for Line-Voltage Thermostats
To increase energy efficiency in new buildings, a requirement for mandatory maximum differential settings for thermostats took effect on January 1, 2007 under the provincial Energy Efficiency Act and Energy Efficiency Standards Regulation. This requirement ensures that individual room heaters maintain a steady temperature, thereby using less energy.
Effective January 1, 2008, all thermostats used with line-voltage (120-240V) electric heaters, such as electric baseboards and fan-forced unit heaters, must control the room temperature within a maximum differential setting of 0.5°C and a maximum droop of 2.0°C, as per CSA Standard C828-06. This applies to wall-mounted, built-in, and two-component type thermostats. Low voltage thermostats for furnaces, including those using gas or electric forced air, are not affected. Compliance with this regulation will be monitored for building permits taken out on, or after, April 4, 2008.
The heat produced by the wiring of line-voltage thermostats (primarily bi-metallic) can affect their temperature readings, making them less accurate. Thermostat droop occurs when the heat of the thermostat’s wiring causes it to sense that the room is warmer than it actually is, and switch off before the room is at the set temperature. Thermostat droop is more severe in cooler weather.