Install Instructions

The basin required for both effluent and sewage applications must be sealed and vented to meet health and plumbing code

requirements. These pumps are not to be installed in locations classified as hazardous in accordance with the National Electric Code,

ANSI/NFPA 70. The diameter should be a minimum of 18" and the depth a minimum of 24". (These are minimum requirements. A

larger basin may be required in both effluent and sewage applications depending on local codes and the number of fixture units

entering the system. Check with the local authorities or contact Liberty Pumps if you are unsure of the proper basin size.) Installation

should be at a sufficient depth to ensure that all plumbing is below the frost line. If this is not feasible, remove the check valve and size

the basin and/or adjust pump differential to accommodate the additional backflow volume.

A. Excavation: Excavate the hole as small as possible, with a minimum recommended 8" diametrical clearance around the tank.

Never place the basin directly in contact with rocks or other sharp objects. Place only fine, 1/8" to 3/4" pea gravel or 1/8" to 1/2"

washed, crushed stone as bedding between the basin and the hole walls. Do not use sand or native soil as backfill. Properly

compact underneath the basin to provide a solid, level base that can support the weight of the filled basin.

B. Inlet Connection & Initial Backfill: Only fine, 1/8" to 3/4" pea gravel or 1/8" to 1/2" washed, crushed stone should be used

around the bottom of the basin to hold it in place. Do not use sand or native soil as backfill. Make the inlet connection as required

for your basin.

Liberty P370 & P380-Series: The Liberty P370-& P380 Series basins have a 4" inlet molded to the side of the tank. This inlet is

sized to accept a 4" no-hub type coupling. Connect the gravity drainage line from the fixtures to this

hub.

Other Basins: Other Liberty basins provide a 4" caulking hub or pipe grommet inlet. Hubs utilize caulking material or

rubber donuts; grommets are a simple slip-fit. Connect the gravity drainage line from the fixtures to this

opening. (Other inlet sizes available – consult factory.)

C. Final Backfill: Large rocks, clods, and foreign objects should be kept out of the backfill material. Only fine, 1/4" to 3/4" pea

gravel, or 1/8" to 1/2" washed, crushed stone is recommended. Do not use sand or native soil as backfill. Mound the backfill

slightly and allow for natural settling. Provide access to the basin cover for maintenance and service.

Do not exert heavy pressure or run heavy equipment on the backfill material as this could cause the

tank to collapse.

For 3-Phase pumps, check for proper rotation before installing pump into basin (see Fig. 1).

If the basin is already installed, proceed

to Installation of the Pump.

2. The Basin

3. Installation of the Pump

Check three phase pumps for proper

rotation prior to installing pump(s) in

basin. To change rotation, reverse any

two of the three power leads to the

pump. Code the wires for

reconnection after installation.

Bottom View

Fig. 1 – Proper impeller rotation,

three phase models