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At Pump Products we recommend carrying out periodic health checks to keep your pump system functioning at maximum efficiency and to minimize repair and replacement costs down the road.

The pump curve drawings we provide in the “Manuals” tabs of most of our hydronic pump models from premium manufacturers ranging from Armstrong to Zoeller, are a good starting point for establishing optimal system operation.  Once you’ve sized and selected the perfect pump model, be sure to ground-truth it’s operation within your system for the first month to establish a baseline against which to measure it’s future performance.

Over time, a pump that begins to operate off it’s Best Efficiency Point (BEP) will incur excessive parts wear. Cavitation is another problem that can effect pump performance over time. This occurs when the pressure at the suction end of the pump, less the fluid’s vapor pressure, is too low. In general, as a pump wears, and internal clearances increase, it’s ability to generate pressure will decrease.

Incorporate the following checks into you pump maintenance program to address these and other common wear issues:

Performance monitoring and system analysis.  Five parameters should be monitored to gauge how a pump is performing: suction pressure, discharge pressure, flow, pump speed and power.  Current transducers offer the most basic and cost-effective power monitoring solution. Measure input voltage, power factor and motor efficiency to determine the actual shaft horsepower being transmitted to the pump. Low voltage pump load monitors provide a good means of checking for under-load and over-load conditions that result in mechanical seal damage or pump failure.

Vibration monitoring. Vibration analysis readings can be taken on the motor outboard and inboard bearing housings in vertical and horizontal directions. An axial vibration measurement should also be taken on the pump.

Bearing temperature. Mounting a temperature sensor to the bearing housing will alert you of possible lubrication breakdown. An alternative method is to aim an infrared gun at a point on the bearing housing where the temperature reading is going to be taken.

Visual inspection. Walk-arounds are part of any preventive maintenance program and can detect cracking, leaking, corrosion and other problems before pump failure occurs.

Even in the best circumstances, a pump can operate outside its best efficiency point. Once installed, a pump’s performance should be monitored and adjustments — such as an impeller trim or speed change on the variable frequency drive — should be made. Keeping precise, up-to-date pumping system data will make pump adjustment, repair and replacement a lot easier down the road.