Head-to-Head Comparison · 1/3 HP Class
Liberty Pumps 257 1/3 HP Cast Iron Sump Pump vs. Pentair Myers 218 1/3 HP Hydromatic Heavy Sump Pump (20ft)
Engineering comparison between the Liberty Pumps 257 1/3 HP Cast Iron Sump Pump and Pentair Myers 218 1/3 HP Hydromatic Heavy Sump Pump (20ft). Flow curves, switch durability, and technical verdict.
218 1/3 HP Hydromatic Heavy Sump Pump (20ft)
The Liberty Pumps 257 1/3 HP Cast Iron Sump Pump delivers 2,040 GPH at 10' head compared to 2,100 GPH for the Pentair Myers 218 1/3 HP Hydromatic Heavy Sump Pump (20ft). If your basement requires maximum flow throughput, the Pentair Myers holds the hydraulic advantage. For tight sump pits, compare the minimum basin clearances: 10" vs 12".
Specification Comparison Matrix
| Specification | Liberty Pumps 257 1/3 HP Cast Iron Sump Pump | Pentair Myers 218 1/3 HP Hydromatic Heavy Sump Pump (20ft) | Advantage |
|---|---|---|---|
| Discharge Flow @ 10' Head | 2,040 GPH | 2,100 GPH | Pentair Myers +60 GPH |
| Shut-Off Head | 21.0 ft | 22.0 ft | Pentair Myers +1.0 ft |
| Switch Mechanism | VMF Magnetically-Coupled Vertical Float | Vertical Float Switch | Vertical Clearance |
| Housing Material | Class 25 Cast Iron | Heavy Cast Iron | Thermal Heat Sink |
| Minimum Basin Diameter | 10" | 12" | Basin Fit |
| List Price | $264.00 | $299.00 | Lower Initial Cost |
Choose 257 1/3 HP Cast Iron Sump Pump If:
- You require 2,040 GPH discharge capacity at standard 10' head.
- Your installation prioritizes Class 25 Cast Iron for continuous motor heat dissipation.
- You prefer the VMF Magnetically-Coupled Vertical Float switch mechanism.
Choose 218 1/3 HP Hydromatic Heavy Sump Pump (20ft) If:
- You need 2,100 GPH flow capacity at 10' dynamic head.
- Your sump pit accommodates a 12" clearance footprint.
- You favor the Vertical Float Switch actuation design.
Hydraulic Performance & Head Sizing
When operating at 10 feet of Total Dynamic Head, the Liberty Pumps 257 delivers 2,040 GPH versus 2,100 GPH for the Pentair Myers 218-20FT. Pumping capacity curves indicate that both models handle standard residential foundation drainage effortlessly.
Switch Technology & Pit Clearance
The Liberty Pumps employs a VMF Magnetically-Coupled Vertical Float requiring a 10" pit, whereas the Pentair Myers utilizes a Vertical Float Switch suited for basins with at least 12" clearance. Ensuring your pit allows uninhibited float movement is essential to preventing switch hang-ups.