Rola-Chem 2" PVC 40-140 GPM Top Mount Flowmeter, 570351T

The Rola-Chem 570351T is a top mount flowmeter for 2 inch schedule 40 PVC pipe, reading 40 to 140 GPM, or 151 to 530 LPM on the metric scale.

Why measure flow

Pressure gauges tell you what the filter is doing. Only a flowmeter tells you how much water is actually moving, which is the number that matters for turnover, for heater minimum flow, and for any code that specifies a rate. On a commercial system it is often required equipment. On a residential one it is the fastest way to know whether a variable speed pump is really doing the job at the speed it has been set to.

Installation

The meter goes into the top of a horizontal run, so the scale reads upward. Flowmeters need undisturbed water to read honestly, which means a straight length of pipe on both sides of the meter and plenty of distance from elbows, tees and valves. Crowding it against a fitting produces a reading that swings or sits high. Rola-Chem also builds side mount and vertical mount versions of this range for runs where a top mount will not work.

Service

It is rated for water up to 200 degrees F and it is built to be opened and cleaned. When a reading drifts, the sight tube and the float are the first things to look at, because scale and debris will hold the float away from its true position long before anything mechanical fails.