Series 1250 Pneumatic Chemical Injection Pump
Operating Manual
Page 4 of 19
CAUTION: Under no conditions should the pump be oriented so the suction check valve is above the
centerline of the motor, such as upside down. Doing so may cause chemical leakage to collect
on the motor, breach the motor seals, and be atomized into the environment.
1.1.3 CheckPoint recommends vertical mounting for its pumps where possible. This allows the suction check valve
to have gravity assistance in closing. However, you may also mount the pump in other orientations, subject to the
condition that the chemical head should be no higher than level with the motor. If mounting will be other than
vertically, you must order your pump with a spring-loaded suction check, or order the appropriate suction check
spring sent to you prior to installation. For placement on a horizontal surface or for mounting to a skid or other
fixed horizontal or vertical surface, CheckPoint recommends using the mounting bracket specifically designed for
this series pump.
1.1.4 CheckPoint recommends use of a calibration gauge for your assurance of proper pump function and chemical
delivery rate. Please read the section in this Guide entitled
3.2.1 Setting Pump Speed Using a Calibration Gauge
for
more information. The proper position of the calibration gauge (labeled #5) is shown in Figure 1.
1.1.5 The Series 1250 does not require flooded suction or positive chemical pressure to prime, and can therefore
be mounted above the chemical container. For a chemical with average viscosity, the pump will pull air out of the
chemical line and prime from up to twelve feet above the liquid level in the tank. This feature is dependent upon
proper packing adjustment and adherence to all points made in Paragraph 1.1.6 below.
1.1.6 ALL VALVES, FITTINGS, AND PIPING BETWEEN THE SOURCE OF CHEMICAL AND THE PUMP’S SUCTION
CHECK VALVE MUST BE 100% BUBBLE-TIGHT AND FULLY COMPATIBLE WITH THE CHEMICAL BEING DELIVERED
AND WITH EACH OTHER. FAILURE TO ADHERE STRICTLY TO THIS RULE WILL LEAD TO GAS BUILD-UP IN THE
CHEMICAL HEAD AND LOST PRIME. SPECIFICALLY:
1.1.6.1 Any fitting or screw-on joint without Teflon
TM
tape or other acceptable sealant may allow air at atmospheric
pressure to enter the suction tubing, even if no chemical leakage is visible.
1.1.6.2 Dissimilar metals, when joined together in the suction pipe work may react with each other, creating gas
bubbles that will end up being carried into the pump head. CheckPoint generally recommends all suction
components, including all tubing, piping, fittings, and valves, be of similar material, preferably stainless steel or other
chemically resistant metal.
1.1.6.3 Incompatibilities between the chemical and the metallic elements in the suction pipe work can also create
such gas bubbles. In particular, some acids require Hastelloy™ or PVC fittings and tubing, while other chemicals may
only require 316 SS.
1.1.7 The pump may be clamped to a skid or other surface in a number of ways, however, clamping around the
outside of the pump reduces accessibility during maintenance and troubleshooting and is therefore not
recommended. Also, aggressive clamping around the air cylinder of the motor has sometimes been found to deform
In Figure 1, the pressure relief valve, secondary chemical filter, vent line, and pressure regulator are
optional under certain conditions but are highly recommended.
CAUTION: It is necessary to attach a vent tube to the top of all calibration gauges, chemical tanks, and
tank level gauges. The height of the top of each vent tube should always be greater than the
highest possible liquid level in the system, and the tube should have means to prevent water
entry, such as a 180 degree bend.
CP/MAN-PRD-015 REV. 15 EFF. DATE: 07/08/2022
