QwikSEER White Paper

Unfortunately, HVAC installers do not perform efficiency optimization tests when selecting the

appropriate airflow rate, so there is no way to know if the blower is operating at the conditions

that optimize system performance.

Even if HVAC technicians could perform a system efficiency optimization test when selecting

the blower setting, the optimal blower airflow can change over time because of environmental

changes. For PSC blower motors, changes in the system pressure drop, caused by such things as

a dirty air filter, will make a more dramatic change to the airflow.

Unlike typical digital thermostat variable speed system installations, which have complicated and

costly ECM motor power electronics, Mainstream’s QwikSEER+ blower control module

automatically accounts for changing installation and environmental conditions each time the

cooling mode is activated and does so with a lower-cost PSC motor configuration.

Mainstream’s patent-pending QwikSEER+ WattSaver control board uses simple relays to turn a

reliable, inexpensive fixed-speed PSC motor into a three-speed motor, yielding much of the

benefit provided by a variable-speed ECM motor (which optimizes airflow with environmental

changes) at a fraction of the cost and with potentially improved reliability.

When the system starts in cooling mode, QwikSEER+ operates the PSC blower motor in

different speeds, compares system operating conditions for the different fan speeds, and

determines the optimal fan speed to maximize performance. This flexibility allows QwikSEER+

to optimize air handler blower speed while accounting for all system conditions: outdoor air

temperature, indoor air temperature and humidity, supply ducting restrictions, and air filter type

and status.

Independent laboratory testing was conducted by Intertek (Plano, Texas) following the

ANSI/ASHRAE 37 test protocol. Running a residential 14 SEER air handler and condensing unit

(80 °F indoor, 97 °F outdoor temperatures) with a QwikSEER+ installed resulted in an EER

improvement of 7.4%. Using the same condensing unit and temperature conditions with a

residential furnace unit (with QwikSEER+ installed), the EER improved by 10.5%. On cooler

days, (82 °F outdoor temperature), the EER improvements for air conditioning and furnace units

with the QwikSEER+ installed increased to 10.9% and 12.9%, respectively. These results are

displayed in Figure 1. To view the Intertek EER test report, go to www.Qwik.com.

Lower airflow rates also improve humidity removal. When a residential SEER 14 air conditioner

with the QwikSEER+ installed was tested for the ability to remove humidity (with the return air

at 80 °F, and 51% relative humidity), the QwikSEER+ WattSaver improved humidity removal

rates by up to 566%, as shown in Figure 2. This increased moisture removal can significantly

improve indoor comfort while also inhibiting the formation of mold, thus improving indoor air

quality. By connecting the optional humidity sensor (QT6001), the QwikSEER+ control board

will also optimize the system for the fastest humidity removal during high-humidity situations.

The Intertek Humidity Removal test report is also at www.Qwik.com.

Unlike a variable-speed ECM motor with a digital thermostat, QwikSEER+ does not have

complicated digital control electronics or complicated power electronics, which can increase cost