PSC vs. ECM Motors: Know Their Differences

24 / 7 Emergency Service Available. Call Us Now: 1.844.894.6832


[BACK]
PSC vs. ECM Motors: Know Their Differences

Posted On: October 19, 2016

PSC vs. ECM Motors: Know Their Differences

The heating, ventilation and air conditioning (HVAC) industry uses a variety of motor technologies in its equipment. Historically, the two predominant motor types have been permanent split capacitor (PSC) single speed motors and electronically commutated motors (ECM) with variable-speed capability. HVAC professionals understand the key differences between these motor types. This article aims to share those differences to you today. 

PSC Motors 

For many years, PSC single-speed motor technology has been the standard in the HVAC industry. It represents the highest installed base. 

PSC motors are considered single-speed (speed refers to rate of rotational motion) because they have no internal controls that can be programmed automatically to vary the rotation of the motor over an operating range. In order to make PSC motors more flexible for various applications, speed taps are included to allow the mechanical contractor to manipulate the motor’s speed to ensure that the correct amount of airflow is delivered. There is, of course, a limit to the amount of static pressure the motor can handle, so it is important to keep in mind the optimal performance and safety. As static pressure increases, a PSC motor’s performance tends to drop off because it cannot adjust torque or speed. 

Because of its design, there are some disadvantages intrinsic in PSC motors. They are less efficient than other motors because they consume more watts. They are not ideal for continuous fan operation because since they run close to full speed, they use more energy than what the function requires. This also makes them less attractive for other continuous filtration applications. They are also the least quiet among the motor technologies. They do not offer customized airflow patterns that are often critical when it comes to managing humidity. 
 


twintechchart-image

ECM Motors 

ECM variable speed motor technology is highly variable and is ideal for various advanced applications. 

ECM technology is based on a direct current (DC) design that is more efficient and it runs cooler than AC PSC motors. They are, in fact, approximately 80% efficient compared to the 60% efficiency rating of PSC designs. ECM motors are programmable. In the case of a failure, the control or the motor can be replaced without having to replace the entire unit. They are also designed to run over a wide range of speeds, making them ideal for delivering airflow in a multitude of system designs. They also draw the least amount of watts, making them the most efficient motor technology. They are also the quietest among the motor technologies since they have the ability to ramp up and down slowly, making them ideal for certain applications with noise concerns. 

When it comes to disadvantages, ECM variable-speed motors come at a premium cost. 

To see the difference in performance between the two types of motors, check out this chart:


 


dfd

*Chart data courtesy of: Biemayer, P., Lutz, J., & Lekov, A. (2004). Measurement of airflow in residential furnaces*




[BACK]

See What Our Customers Are Saying:

by dianeramsden on Twintech Heating and Cooling

Our air conditioner failed. Made a call and within 15 min a technician was at our door.
The issue was fixed and many suggestions were provided.
Thanks to Mitch. Great service !

by Kazuko on Twintech Heating and Cooling

Our furnace was rattling, as soon as we put our air conditioner on this past week. We had researched looking for a company that was Registered with Better Business Bureau, and this company TwinTech, had A+ Rating. Scott, was immediately helpful via text/phone and sent his technician as soon as he was able...Mitchell/technician provided great professional service. Thank you TwinTech.
Sean and Debbie

by ANOOP on Twintech Heating and Cooling

I contacted various companies when looking to install a new furnace and I found Twintech to be transparent with their communication and approach. They had options to suit my various requirements and the price vs quality was very good. The after installation communication was also very good and they answered all queries I had.

by Private User on Twintech Heating and Cooling

My furnace broke down last month. The team was quick to respond, courteous, professional and mindful of COVID-19 concerns. I highly recommend them if you are considering replacing or servicing your HVAC equipment.

by Private User on Twintech Heating and Cooling

I was very happy with the installation and price. I would definitely recommend. Thank you Twintech.

by Dorothy on Twintech Heating and Cooling

Had furnace and air conditioning unit put in. They did an excellent job great price and everything clean as can be, I was very pleased

by Barry on Twintech Heating and Cooling

All winter I have had an issue with very little heat reaching the 2nd floor of our home. After this past winter ended I decided to look into this. I found Twintech Heating and Cooling on line and started the process. After explaining my problem I had a call form Twintech and the tech came out and walked through things with me. The problem was the heating vent pipe had been dropped down in size by someone years ago causing little heat reaching the 2nd floor. Further into checking out the older furnace and AC they found a few things not properly installed by the last install of the old furnace and also that the AC was on it's last legs. I asked for a quote and waited a few days and we decided to go ahead with Twintech. They called a few days before to set up an installation time and date. The day of the install the guys were a half hour early which was a plus. The day of the install was great, the guys worked away removing the old furnace and AC.After which they installed the new furnace and AC. After they cleaned up the basement with all their tools and scrap metal etc. they came back inside to walk thru what they did. They also tested both the furnace and cooling systems to make sure everything worked and I the customer was happy. I now have heat on the 2nd floor for next winter. The guys from Twin tech were very professional. Their work habits and knowledge of the job was excellent. Their workmanship was just excellent, it was just up there with my standards as a homeowner. I am very pleased to have chosen Twintech for my new furnace and AC.. If I had to rate this experience with Twintech this company is a 10 in my books.Product,workmanship and customer care says it all.

by Craig in Whitby on Twintech Heating and Cooling

I called Twintech during the Covid 19 crisis because our furnace was broken and it was still very cold during the nights. Dave answered all of my questions by phone but wanted to come have a look but only if our family felt comfortable having someone visit during the uncertainty surrounding the pandemic and was able to attend that very same affternoon.

He was very courteous and informative but most importantly he respected his and our safety by wearing medical gloves in our home and maintaining proper physical distancing. He reviewed the various options of the products that suited our needs going over not only price but quality of workmanship, warrantees and where the product was manufactured which were all important factors in making such a large purchase. You could tell that Dave had been in this industry for a very long time.

The installation was done by a fine young gentleman the very next day and we now have a toasty warm home to ride out this crisis in while humming along at 96% efficiency!

I would recommend this very professional, small family business for anyone in need of HVAC equipment or maintenance.

by Lucy in Markham on Twintech Heating and Cooling

My special thanks to Twintech teams! They had replaced my furnace and A/C, and installed a new humidifier for me 2 weeks ago. Dave, the sales manager, not only provided me with an honest quote on the best HVAC products with best quality and warranties, he also arranged portable heaters for me and sent supporting docs to energy company for energy audit. Above and beyond service!

Greg, Grant, Mitch had worked tirelessly and professionally to perform the HVAC installation. They worked with professional tools, and performed proper measurement readings after installation. They are very patient with all my questions, and very pleasant to communicate.

Great work guys! This company sure knows their products and they stand behind their services. My home comfort level has improved! I am glad that I can support an ethical and honest local family business.

by ddame on Twintech Heating and Cooling

Professional, flexible on price and delivered on time...well done. All you can ask for when getting a new furnace.