Installation
Installing Two Pumps for Tandem Operation
19
Installing Two Pumps for Tandem Operation
When greater flow rates are needed, two pumps may be required in the same piping system by means of a
manifold. If they are installed according to the illustration, a tandem system offers backup support so operations
can continue if one pump stops working. Install the pump as outlined above with the following additions.
If a siphon system is required, each pump must have 3/8 inch siphon vacuum line attached to the same location on
the siphon line (reference Figure 9).
Adjust the Pressurstat (see “Adjusting the Pressurstat Line Relief Pressure” on
page 24) on both packers to maximum relief pressure by rotating fully clockwise. If
maximum pump pressures are NOT a minimum of 5 psi below the Pressurstat relief
setting then proper check valves with pressure relief are required to be installed in the
discharge line of each pump to prevent product from being pumped through the
pressure relief system of the adjacent pump when it is not operating. Readjust the
Pressurstat to the desired pressure relief value for proper operation of the siphon
system.
Installation of a ball valve is recommended on the discharge side of the pressure relief check
valve. This will aid in troubleshooting and line testing.
Figure 10 illustrates the requirement for in-line, pressure relief type check valves. It is not a
recommended guide for installation of piping downstream of the check valves.
Figure 10. Tandem Pumps
