To accommodate changing system demand, most of today’s modern Electronically Commutated Motor (ECM) circulators automatically calculate the lowest achievable operating-efficiency threshold. As a result, this technology produces the bare minimum of output necessary to ensure ideal comfort without requiring direct human involvement. As an outcome, when compared to other circulators in its category, the ECM circulator is intended to decrease power usage by at least 50%, if not more.
In addition, circulator pumps with ECM motors, in general, provide sophisticated speed control. Speed-controlled pumps alter their output in response to changing demand, which can be caused by changes in outdoor temperature, sunshine levels, general activity, and other heating sources. The advantage of having a more efficient ECM motor pump is that it saves a lot of energy, which translates to cost savings while maintaining performance. More information on ECM pumps can be found through this link.
In an interview for Plumbing and Mechanical with Kirk Vigil, business development manager for Grundfos Pumps Corporation, Vigil explains ECM efficiency. The first question that the author asked was what makes a “smart” or high efficiency pump smart and what are the components of these units? Vigil said:
“There are two primary components that distinguish “smart” or high energy-efficient pumps from traditional single and three-speed pumps. First is the use of an ECM, or electrically commuted motor, a.k.a. permanent magnet motor versus standard induction/asynchronous motors. ECM motors are compact and powerful. ECM motor construction and efficiency alone can provide 50% energy consumption reductions. Second, incorporating speed control within the pump, variable speed pumping, allows the pump to be sped up or slowed down based on the environment it is operating in. Degrees of “smart” can be debated; however, at Grundfos we use advanced software, AUTOADAPT, within microprocessors in the pump control head. AUTOADAPT uses internal sensors and advanced algorithms to monitor the actual and dynamic changes in the system and continually control the pump speed to satisfy the system demand.”
The interview continues with questions about the advantages, service life and maintenance, and fuel costs of a Grundfos high-efficiency variable speed pump over others. Vigil said that the benefits are mostly related to lower energy use but decreased utility expenses, which is reflected in operational costs. However, comfort is the most important or best advantage of employing high-efficiency variable speed pumps and circulators. When paired with an intelligent control, these pumps can precisely deliver the correct flow quantity to meet a system requirement, such as a need for heating or cooling—pumps with a fixed speed run at full speed by definition. As a result, unless the system maintains media temperatures in any other way, this can have the same impact as uncontrolled forced air systems. During system cycles, occupants may notice a temperature variation. Controlled appropriately, variable-speed pumps may balance out those cycles and give steady, uninterrupted comfort.
High-efficiency pumps and circulators using ECM motors often have a higher service lifespan than circulators with induction motors. Because of the improved motor design, there is less wasted energy, and most manufacturers have updated the quality of components in these pumps, making them more robust and lasting. Vigil continues to add that manufacturers and models may have different maintenance requirements. Grundfos circulators, particularly high-energy efficient wet rotor circulators, are almost maintenance-free.
There are growing worries that these high-efficiency pumps and associated ECM motors with strong magnets accumulate more iron oxide, or magnetite, and cause problems. In hydronic heating systems, iron oxide and magnetite combine to generate a black sludge. The entire architecture of Grundfos’ wet rotor circulators guarantees high resistance to contaminants like magnetite. Particles are minimized in their rotor cans thanks to resistant materials, coatings, and flow designs. All Grundfos circulators must handle high amounts of iron oxide and magnetite as a design criterion. Because of the design intricacy and system size, fuel cost reductions vary from system to system. In general, Grundfos estimates that customers may save up to 85% on electrical energy and 50% on petrol. Grundfos has seen case studies and field testing with percentages lower and higher than this. Return on investment has also ranged from a few months to three years.
To read a case study on Grundfos Circulator Pumps with ECM technology, follow this link.
More information on Grundfos Circulator Pumps with ECM technology can be found on their website.
Shop Grundfos ECM pumps here.