Parker Pure Water Series, Installation Operation & Maintenance, Page: 144 / 175

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INLET CONDITION CHECKLIST
Review this checklist before operation of system. It is critical that all factors are carefully considered and met.
INLET SUPPLY
Inlet supply should be adequate to accommodate the maximum flow being delivered by the pump.
1. Open inlet valve and turn on supply to avoid starving the pump.
2. Avoid closed loop systems, especially with high temperature, ultra-high pressure or large volumes. Conditions
vary with regulating/unloader valve.
3. Low vapor pressure fluids, such as solvents, require positive heads to assure adequate inlet supply.
4. Higher viscosity fluids require that the pump be flooded to 60 PSI to assure adequate inlet supply.
5. Higher temperature fluids tend to vaporize and require positive heads to assure adequate inlet supply.
6. When using an inlet supply reservoir, size it to provide adequate supply of fluid to accommodate 6-10 minutes
retention time at the rated GPM (however, a combination of system factors can change this requirement).
Provide adequate baffling in the tank to eliminate air bubbles and turbulence. Install diffusers on all return lines to
the tank.
INLET LINE SIZE
Inlet line size should be adequate to avoid starving the pump. Pump suction should never operate in a vacuum.
1. Line size must be sufficient to allow free flow of influent fluid at the pumping flow rate. Minimize the use of thick-
walled fittings, tees, 90-degree elbows, or valves in the inlet line of the pump to reduce the risk of flow restriction,
vacuum, and cavitation.
2. The inlet line MUST be a FLEXIBLE hose, NOT a rigid pipe, and REINFORCED ON SUCTION SYSTEMS to
avoid collapsing.
3. The simpler the inlet plumbing, the less the potential for problems. It is recommended to keep the length, number
of joints, and the number of inlet accessories to a minimum.
4. Use pipe sealant as appropriate to ensure airtight positive sealing pipe joints.
INLET PRESSURE
Inlet pressure should be between flooded (zero) to 60 PSI.
1. High RPM, high temperatures, low vapor pressures, or high viscosity reduces inlet pressure. The pump may
require a pressurized inlet to maintain adequate inlet supply.
CAUTION
DO NOT RUN PUMP DRY.