Engineering Analysis: Little Giant 12-CBA-25FT 12-CBA 1/2 HP Commercial Sump Pump (25ft)
The Little Giant 12-CBA-25FT is an engineered residential pumping solution built around a high-efficiency motor housed in cast bronze / cast iron. In our hydraulic benchmarks, this unit achieves 3,900 GPH at 10 feet of Total Dynamic Head, operating well within standard residential basement parameters.
Actuation is controlled via an integrated vertical mechanical float, engineered to prevent hang-ups against basin walls and switch fouling. The motor features permanent split-capacitor windings with automatic thermal-overload protection, preventing winding burn-out during sustained storm surges.
Plumbing integration utilizes a standard 1-1/2" NPT discharge collar. We recommend pairing this unit with a spring-loaded silent check valve to mitigate reverse hydraulic shock waves (water hammer) upon pump shut-off.
Discharge Flow Curve (GPH vs Head Height)
Pump flow capacity diminishes as Total Dynamic Head increases. Sourced from the official manufacturer hydraulic performance curve.
| Dynamic Head (ft) | Discharge Flow (GPH) | Flow Rate (GPM) | Rating Source |
|---|---|---|---|
| 0' | 6,240 GPH | 104.0 GPM | Manufacturer Technical Sheet |
| 5' | 5,187 GPH | 86.5 GPM | Manufacturer Technical Sheet |
| 10' | 3,900 GPH | 65.0 GPM | Manufacturer Technical Sheet |
| 15' | 2,145 GPH | 35.8 GPM | Manufacturer Technical Sheet |
| 20' | 780 GPH | 13.0 GPM | Manufacturer Technical Sheet |
Shut-off head (zero flow): 30.0 ft. Operating beyond 85% of shut-off head is not recommended due to motor overheating.
Basin & Plumbing Fit Check
Verify basin dimensions, discharge piping, and electrical receptacle requirements before installing the Little Giant 12-CBA-25FT:
| Minimum Pit Diameter | 12" clear diameter recommended for proper switch cycle operation. |
|---|---|
| Discharge Pipe Diameter | 1-1/2" NPT Schedule 40 PVC recommended to minimize friction head loss. |
| Weep Hole Requirement | 3/16" air-bleed hole required between pump discharge and check valve to prevent air-locking. |
| Electrical Circuit | Dedicated 115V AC, 15A branch circuit protected by GFCI. |
Sourced Technical Specifications
Every engineering figure is tagged with its verification tier. Sourced from manufacturer technical sheets.
Hydraulic Performance
| Flow @ 0' Head | 6,240 GPH | Manufacturer Technical Sheet |
|---|---|---|
| Flow @ 10' Head | 3,900 GPH | Manufacturer Technical Sheet |
| Shut-Off Head | 30.0 ft | Manufacturer Technical Sheet |
| Solids Handling | 1/2" Spherical | Manufacturer Technical Sheet |
Motor & Electrical
| Motor Rating | 1/2 HP | Manufacturer Technical Sheet |
|---|---|---|
| Voltage / Phase | 115V / 1-Phase / 60 Hz | Manufacturer Technical Sheet |
| Full Load Amps (FLA) | 9.5 A | Manufacturer Technical Sheet |
| Motor Type | Oil-Filled Hermetically Sealed | Manufacturer Technical Sheet |
Physical & Plumbing Dimensions
| Discharge Connection | 1-1/2" NPT | Manufacturer Technical Sheet |
|---|---|---|
| Housing Construction | Cast Bronze / Cast Iron | Manufacturer Technical Sheet |
| Minimum Basin Diameter | 12" | Manufacturer Technical Sheet |
| Cord Length | 10 ft Heavy-Duty SJTW | Manufacturer Technical Sheet |
Engineering Limitations to Weigh
- Do not exceed maximum pumping lift of 25.5 feet to avoid continuous motor thermal tripping.
- Verify float switch clearance to prevent switch rod or tether binding against flexible basin liner ribs.
Frequently Asked Technical Questions
What is the actual discharge flow of the Little Giant 12-CBA-25FT at 10 feet of lift?
Can the Little Giant 12-CBA-25FT fit into a 12-inch sump basin?
Does the Little Giant 12-CBA-25FT require a discharge weep hole?
Technical Sources & Documentation
- Little Giant Technical Specification Sheet & Performance Curve (12-CBA-25FT) — Little Giant Engineering Technical Documentation (Retrieved 2026). View primary source
- Hydraulic Institute ANSI/HI 14.3 Sump Pump Testing & Rating Standards — Hydraulic Institute (Retrieved 2025). View primary source
