Modern furnaces contain many advanced features that help improve system efficiency and indoor comfort. One of the more effective of these features is the electronically commutated motor, or ECM. These devices, commonly known as variable-speed blower motors, contain built-in speed and torque controls that allow the motor to run at different levels while distributing warm air from the furnace. This allows them to operate only at the speed that is needed to maintain indoor temperature settings, which saves significant amounts of energy and improves heating system performance.
In the past, furnaces usually contained permanent split capacitor, or PSC motors. These types of motors are very common and inexpensive, but are considerably less efficient than the ECM type. The biggest disadvantage of PSC motors is that they can run at only one speed, shutting off and on in response to temperature changes and heating demands. Since they only run on high, they consume the greatest amount of energy every time they switch on.
In contrast, ECM motors run at varying levels depending on the comfort settings you’ve selected and the changing temperatures inside your home. When they start, they usually run at about 2/3 speed. If the system’s thermostat detects that heating is still needed after about 10 minutes, the ECM increases to full speed. This variable range of operation means the motor can run more often at lower levels, which improves overall efficiency and reduces wear on the unit.
An electronically commutated motor offers other advantages over older-style motors:
- ECMs use up to 75 percent less electricity than older motors.
- ECMs are quieter than other types of motors.
- ECMs can be set to run on fan-only. This improves indoor air quality by constantly circulating air through the system’s filters without consuming fuel or energy for heating.
Heating and air conditioning customers in Calgary and the surrounding area have a trusted and reliable resource in Arpi’s Industries Ltd., a company with more than 50 years of professional experience in the HVAC industry. Contact us today for more information on how using a variable-speed electronically commutated motor in your HVAC system will improve efficiency, indoor comfort and savings.
Our goal is to help educate our customers in Calgary, Alberta about energy and home comfort issues (specific to HVAC systems). For more information about Electronically Commutated Motors and other HVAC topics, download our free Home Comfort Resource guide.
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