If you’re like most Phoenix-area residents, your air conditioner is one of the biggest contributors to your monthly electric bill. If you have an older A/C unit, you can reduce your electric bill by replacing it with a new high-efficiency system. However, if you don’t have the funds to spend on a completely new system, an A/C motor upgrade can improve your motor efficiency and reduce your monthly electric bill.

Many older A/C systems have what’s called a permanent split capacitor (PSC) motor. A PSC has 62 percent efficiency when it’s running at its full load. However, residential PSCs never run at peak efficiency because they’re too noisy. Instead, the typical PSC has a motor efficiency of between 12 percent and 45 percent. In other words, your A/C motor can be a huge energy drain.

In the 1960s, engineers created the electronically commuted motor (ECM). ECMs are much more efficient than the PSC, but until recently they were too expensive for most HVAC systems. The average ECM operated at 65 percent to 75 percent motor efficiency. This means a new motor could be more than six times as efficient as your current A/C motor.

How do ECMs achieve save electricity?

  • They use magnets and bearings to reduce friction as they spin. This means they can move faster than PSCs while using less electricity.
  • Since ECMs have less friction, they run cooler. A typical PSC runs at 90 to 150 degrees and needs additional electricity to stay cool. ECMs run at the surrounding temperature.
  • They contain a computer so that your A/C professional can set them to the most efficient speeds for your home.
  • ECMs start up and stop slowly to reduce humidity. This means you can turn up your thermostat without sacrificing your family’s comfort.

If you live in the Phoenix area and would like to learn more about increasing you’re A/C unit’s motor efficiency, contact Wolff Mechanical. We can help you find cost-effective ways to save energy and reduce your electric bills.