Treatment Plant Operator magazine recently highlighted a demanding real-world demonstration of wastewater blower durability at the Warrensburg, Missouri, wastewater treatment facilities.

The September 2026 article, “A Blower Upgrade Saves 10–20% on Energy,” reports that Warrensburg’s Inovair geared centrifugal blowers have completed more than 20,000 start-stop cycles with only basic routine maintenance. The installation has also remained reliable through the power-quality disturbances that can challenge high-speed blower equipment.

For treatment plants comparing blower technologies, Warrensburg offers an important lesson: efficiency matters, but long-term performance also depends on how a blower handles every startup, shutdown, restart, and unexpected power interruption.

Built for Frequent Start-Stop Operation

Warrensburg operates two sequencing batch reactor (SBR) facilities. Because an SBR repeatedly moves between treatment stages, its aeration blowers start and stop far more frequently than blowers serving many continuous-duty processes.

Each operating cycle requires the blower to accelerate to speed, respond to process demand, shut down, and coast to a complete stop. Over time, that repeated cycling can expose limitations in bearing and lubrication systems that depend on external power or specific operating conditions.

Warrensburg’s Inovair blowers have now surpassed 20,000 start-stop cycles while requiring only basic routine maintenance. That record demonstrates the value of selecting a blower designed around the plant’s actual duty cycle—not simply its airflow and pressure requirements.

Inovair geared centrifugal blowers use fully floating oil-film bearings to support the high-speed shaft. The oil pump is driven mechanically from the input shaft, so lubrication continues whenever the shaft is rotating, including during startup, normal operation, shutdown, and coast-down.

This design maintains a protective oil film between the shaft and bearing surfaces throughout the complete operating cycle. It also enables unlimited starts and stops without the operational restrictions associated with some other high-efficiency blower technologies.

For an SBR facility such as Warrensburg, that capability directly supports the treatment process instead of requiring operators to modify blower operation around equipment limitations.

Voltage sags, generator transfers, utility switching, and power interruptions can trip a wastewater blower offline in a fraction of a second. The high-speed rotating assembly, however, does not stop instantly. It must remain supported as it safely coasts down from operating speed.

Because Inovair’s oil pump is mechanically driven by the rotating input shaft, lubrication continues through an unexpected shutdown—even if electrical power to the blower has been interrupted. This makes the bearing system inherently well suited for facilities that experience inconsistent utility power or frequent generator transfers.

Warrensburg’s experience shows why dirty-power resilience should be considered during blower selection. A blower’s response to abnormal electrical conditions can be just as important to long-term reliability as its performance at a published design point.

Learn more about dirty power and wastewater blower reliability.

The Warrensburg facilities previously relied on aging blowers installed in basement blower rooms. The plants upgraded to outdoor Inovair IM-30 geared centrifugal blower packages, providing modern airflow control, easier service access, and a more comfortable working environment for plant personnel.

The outdoor packages also allowed Warrensburg to modernize its aeration equipment without remaining constrained by the existing basement installations.

Although reliability is the standout result from the Warrensburg installation, the upgrade also improved operating efficiency. According to the results reported by TPO, the plants have reduced energy costs by approximately 10–20%.

Variable-speed control allows operators to match blower output more closely to actual oxygen demand instead of supplying excess airflow. For an SBR, that flexibility helps the blower respond efficiently as demand changes throughout each treatment cycle.

The result is a strong combination of benefits: more than 20,000 reliable start-stop cycles, improved process control, reduced energy use, and straightforward routine maintenance.

Warrensburg’s experience with its initial Inovair installations provided the confidence to order two additional blowers. That follow-up decision reinforces the performance documented in the TPO feature and demonstrates the value of equipment engineered for real wastewater operating conditions.

The project also illustrates why a complete blower evaluation should include duty cycle, start-stop frequency, power quality, turndown, installation environment, serviceability, and lifecycle cost—not only maximum airflow, pressure, or peak efficiency.