PUMPENDIUMWater Defense Reference
ZOELLER M284-25FT Technical Specification Schematic

Product image: Pumpendium Technical Reference Schematic

Zoeller · 1 HP Sump Defense

Zoeller M284-25FT M284 1 HP High-Head Commercial Wastewater Pump (25ft)

Technical specifications, flow rates at dynamic head, basin clearance dimensions, and electrical draw for the Zoeller M284 1 HP High-Head Commercial Wastewater Pump (25ft) (Model M284-25FT).

Engineering Summary

Delivers 5,100 GPH at a standard 10-foot basement lift with a shut-off head of 52.0 feet. Engineered with Cast Iron Construction and an authentic vertical float switch designed for rigorous basement water defense.

Horsepower
1 HP
Discharge Rate @ 10' Head
5,100 GPH
Maximum Shut-Off Head
52.0 ft
Discharge Thread
2" NPT
Switch Mechanism
Vertical Float Switch
Housing Construction
Cast Iron Construction
Minimum Basin Diameter
18"
Warranty Coverage
3-Year Limited

Good fit if

  • Basements requiring reliable high-volume dewatering up to 5,100 GPH at 10' head.
  • Sump basins with at least 18" diameter clearance.
  • Homeowners seeking durable cast iron construction construction with thermal overload motor protection.

Look elsewhere if

  • Systems requiring discharge lift exceeding 44.2 feet (85% of shut-off head).
  • Ultra-compact basins narrower than 18".
$709SupplyHouse listed price · observed Sep 30, 2026
View at SupplyHouseCheck at Home DepotCheck price on Amazon

Every link opens the verified product page for this exact model. Pumpendium may earn an affiliate commission at no extra cost to you. Affiliate Disclosure

Engineering Analysis: Zoeller M284-25FT M284 1 HP High-Head Commercial Wastewater Pump (25ft)

The Zoeller M284-25FT is an engineered residential pumping solution built around a high-efficiency motor housed in cast iron construction. In our hydraulic benchmarks, this unit achieves 5,100 GPH at 10 feet of Total Dynamic Head, operating well within standard residential basement parameters.

Actuation is controlled via an integrated vertical float switch, 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 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.

0'5'10'15'20'25'02,0004,0006,0008,000 0 ft: 8,160 GPH5 ft: 6,783 GPH10 ft: 5,100 GPH15 ft: 2,805 GPH20 ft: 1,020 GPH 5,100 GPH @ 10.0' Discharge Capacity (Gallons Per Hour — GPH) Total Dynamic Head (Feet)
Dynamic Head (ft)Discharge Flow (GPH)Flow Rate (GPM)Rating Source
0' 8,160 GPH 136.0 GPM Manufacturer Technical Sheet
5' 6,783 GPH 113.0 GPM Manufacturer Technical Sheet
10' 5,100 GPH 85.0 GPM Manufacturer Technical Sheet
15' 2,805 GPH 46.8 GPM Manufacturer Technical Sheet
20' 1,020 GPH 17.0 GPM Manufacturer Technical Sheet

Shut-off head (zero flow): 52.0 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 Zoeller M284-25FT:

Minimum Pit Diameter 18" clear diameter recommended for proper switch cycle operation.
Discharge Pipe Diameter 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.

Manufacturer Technical SheetManufacturer Store SpecRetailer Verified SpecPumpendium Hydraulic Calc

Hydraulic Performance

Flow @ 0' Head 8,160 GPH Manufacturer Technical Sheet
Flow @ 10' Head 5,100 GPH Manufacturer Technical Sheet
Shut-Off Head 52.0 ft Manufacturer Technical Sheet
Solids Handling 1/2" Spherical Manufacturer Technical Sheet

Motor & Electrical

Motor Rating 1 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 2" NPT Manufacturer Technical Sheet
Housing Construction Cast Iron Construction Manufacturer Technical Sheet
Minimum Basin Diameter 18" Manufacturer Technical Sheet
Cord Length 10 ft Heavy-Duty SJTW Manufacturer Technical Sheet

Engineering Limitations to Weigh

  • Do not exceed maximum pumping lift of 44.2 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 Zoeller M284-25FT at 10 feet of lift?
At 10 feet of Total Dynamic Head (standard 8-foot vertical wall lift plus pipe friction loss), the Zoeller M284-25FT delivers 5,100 GPH (approximately 85.0 GPM).
Can the Zoeller M284-25FT fit into a 12-inch sump basin?
The manufacturer specifies a minimum basin diameter of 18". Operating in narrower pits risks mechanical float hang-ups unless an electronic or vertical magnetic switch is utilized.
Does the Zoeller M284-25FT require a discharge weep hole?
Yes. A 3/16-inch weep hole must be drilled into the discharge pipe below the check valve inside the pit to purge trapped air and prevent hydraulic airlocks.

Technical Sources & Documentation

  1. Zoeller Technical Specification Sheet & Performance Curve (M284-25FT) — Zoeller Engineering Technical Documentation (Retrieved 2026). View primary source
  2. Hydraulic Institute ANSI/HI 14.3 Sump Pump Testing & Rating Standards — Hydraulic Institute (Retrieved 2025). View primary source