Solenoid-driven diaphragm metering pumps have long been a standard for chemical feed applications. They’re cheap, relatively accurate and essentially disposable.

But let’s face it. These little metering pumps can bring big headaches. Their low suction lift often makes them difficult to restart once they lose prime — and they’re prone to stuck check valves, leakage and clogging. In addition, they often become vapor-locked when feeding outgassing chemicals such as sodium hypochlorite (NaOCl).