ECM technology curbs excessive and under pumping.
by Bob “Hot Rod” Rohr
May 27, 2019

The evolution of electronically commutated motor (ECM) technology into the fractional horsepower market has opened possibilities for building service end users. The world of building systems depends upon circulators for hydronics, including heating and chilled water applications.

Solar thermal has lost some market share in the past few years but is still a viable market for ECM, hereon referred to as smart pumps.

How did pumps get so smart? Once a microprocessor is attached to an efficient motor design, many doors open.

Prior to the release and acceptance of smart pumps, mainly multispeed technology was available for use. While that was a step up from single-speed motors, the market demanded more.

By adding a brain to the package, building circulator pumps can now be further manipulated to almost the exact requirements of the end user.

Performance output, record and display data can be modulated and connected remotely to monitor or adjust. This is in addition to a more efficient motor design. It is not uncommon to experience 50 to 80 percent electrical energy savings from the improved motor design.

There can be a win on the fluid side, also. Current and widely available circulators have the ability to adapt to ever-changing requirements found in zoned systems. Smart pumps have the ability to sense changing flow requirements and reduce or increase flow rates to match and maximize the flow performance.

In building systems zoned with on/off or modulating valves, the smart pumps shine. Simply put, it is like a cruise control on the circulator. Excessive over or under pumping should be a thing of the past.

Much of the high-tech circulator pump technology evolves from ever-increasing energy standards in Europe, home to some of the largest hydronic markets and pump engineering. The color bar graph seen on some pump boxes indicates the standard and how the product performs to it.

The European standard changes occasionally and the bar is set higher. Pump manufacturers seek out engineered equipment that will meet the evolving energy standard requirements.

Regardless of how the system is zoned, whether it is motorized on/off valves, proportional thermostatic valves or zone pumps, there is technology available to fit a user’s application.

The acceptance of this technology has made it more affordable. The early entry versions were nearly four times the price of standard permanent split capacitor (PSC) wet rotor-style circulators. Smart pumps, in addition to their electrical savings, can solve other long-standing problems in buildings.

Excessive velocity and banging or noisy control valves exist in some systems.

With features like auto adapt, the circulator will learn the fingerprint of the system and make flow adjustments to help keep pumps from running off their curve.
Until recently, the common circulator included three pieces:

  • motor
  • bearing
  • pump volute

Selection for small applications was limited. These early workhorse circulator pumps required maintenance and manual lubrication.

When properly sized and cared for, they lasted for years, sometimes decades.

So, as the pump spins, a user can keep their hydronic system’s drama to a minimum.

Tips for Smart Pump Technology

  • Always practice safe pumping.
  • Run the appropriate calculations to size the pump.
  • Consult with representatives or the manufacturer for sizing help on these new “funny curve” smart pumps.
  • Include strainers or separators to keep everything clean and healthy.
  • Install isolation valves and gauge ports for testing, servicing and confirming performance.
  • Ensure good fluid quality. Systems may have plain tap water, a blend of glycols for freeze protection or conditioners to protect multimetal systems. The fluid is the lifeblood of all hydronic systems and circulator pumps know and appreciate attention to that detail.