Series 1250 Pneumatic Chemical Injection Pump
Operating Manual
Page 9 of 19
Occasionally, soon after closing the bleed assembly, you may observe packing leakage. If so, this is
usually due to a loose packing nut. Adjust the packing nut per the instructions in
Section 5.1: Packing
Adjustment
on page 14.
3.1.4 Open the speed control valve by turning the knob counterclockwise. The pump should pick up speed as the
knob is rotated. Continue to turn the knob until the pump is cycling a minimum of 60 strokes/minute. This may take
up to eight (8) turns of the needle valve.
3.1.5 Open the bleed screw 2-1/2 to 3 turns. The pump will begin to pull air and chemical through the chemical
supply plumbing, into the head, and out the port in the bleed valve. Leave the valve open until a solid stream of
chemical pumps out the bleed port with each stroke of the pump.
3.1.6 Reclose the bleed screw until chemical flow through the bleed port stops, then reduce the pumping rate via
the speed control until the pump is cycling at your desired rate.
3.2 Setting The Pump Stroke Rate
3.2.1 Setting Pump Speed Using a Calibration Gauge
The following directions are for setting the pump speed using a calibration gauge. There are a variety of calibration
gauges available, including a complete line of appropriately-sized CheckPoint gauges for every CheckPoint pump.
To ensure that your pump is working as is should and that chemical is being delivered at the rate you need, it is
important to use a calibration gauge.
3.2.1.1 Most calibration gauges are designed to read properly when one full minute of pumping has taken place.
However, if the liquid level drops too fast to allow for a full minute, shorter periods are acceptable. Try to size the
gauge so that at least a 30 second test can be made, however, or a loss of accuracy will result.
3.2.1.2 Proper gauge placement and plumbing is important. Please refer to Figure 1 for appropriate valving and
placement, and for reference numbers as used in this section. The calibration gauge is labeled as number 5.
3.2.1.3 With the pump either running or stopped, open the Gauge Fill Valve (shown as #4 in Figure 1). The gauge
(shown as #5 in Figure 1) should begin to fill. Continue filling until the chemical level is at or near the top markings
on the gauge, then close the Gauge Fill Valve.
3.2.1.4 Now ensure that the CheckPoint pump is running. Take note of the level of chemical in the gauge using the
appropriate scale for the volume units you want to measure the pump’s output in. Usually the gauge will show liters
on one scale and quarts or gallons on the other. It is best to write down the number so that you can calculate flow
accurately.
3.2.1.5 Open the Gauge Fill Valve (#4), and simultaneously close the Chemical Supply Valve (shown as #1 in Figure
1). This isolates the pump and gauge so that the pump is being supplied its entire chemical directly from the gauge.
3.2.1.6 The level in the gauge should begin to fall. (If it does not, or if the level seems to go down and then back
up with each stroke, refer to troubleshooting in
Section 6.1 on page 17
). When the liquid level in the gauge gets
DO NOT OVER-TIGHTEN THE BLEED SCREW. Tighten the bleed screw ONLY until chemical stops
flowing. Applying excess torque to the bleed valve may impair future valve operation.
CP/MAN-PRD-015 REV. 15 EFF. DATE: 07/08/2022
