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Basement Sentry 1200 gph Thermoplastic Diaphragm Switch Water Submersible Backup Sump Pump

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Basement Sentry 1200 gph Thermoplastic Diaphragm Switch Water Submersible Backup Sump Pump is your basement’s quiet guardian against floods. Compact, reliable, and designed to slip…

Zoeller MPN STWB140 In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $224.99. Our online price is $249.99.
$249.99
Includes free shipping on orders over $75 · $8.99 standard below
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About Product Overview

Basement Sentry 1200 gph Thermoplastic Diaphragm Switch Water Submersible Backup Sump Pump is your basement’s quiet guardian against floods. Compact, reliable, and designed to slip into standard sump pits, it activates when you need it most and keeps water where it belongs—outside your living space.

Built with a thermoplastic housing, this submersible backup pump stands up to the damp, challenging environment of a basement. The diaphragm switch delivers precise, steady cycling without the hassles of traditional float switches, ensuring the pump starts and stops reliably as water levels rise and fall. With a robust 1200 gallons-per-hour discharge capacity, it provides substantial protection during heavy rain, rapid snowmelt, or power interruptions—without demanding a lot of space or maintenance.

Key features that make a difference

  • Maximum discharge flow: up to 1200 GPH
  • Submersible design with bottom suction for efficient water pickup from the pit floor
  • Diaphragm switch for consistent, low-maintenance on/off operation
  • Thermoplastic housing resists corrosion and chemical exposure common in sump pits
  • CSA-compliant for safety and reliability in residential settings
  • Compact footprint: 5.7" high, 13.82" wide, 15.7" deep
  • Maximum head: 30 feet, giving you versatility in a range of pit depths
  • Operating temperature range: 40°F to 104°F, suitable for typical basement environments

Who should consider this pump? Homeowners looking for a dependable backup sump solution that integrates seamlessly with existing drainage plans, especially in areas prone to power outages or sudden flooding. It’s ideal for finished basements, crawl spaces, and utility rooms where a compact, durable backup pump can provide peace of mind without crowding the sump area.

Use cases and practical applications

  • Backup protection during heavy rainfall or rapid snowmelt when your primary pump may be overwhelmed
  • Basement weddings or renovations where extra water protection is critical
  • RVs, workshops, or homes with smaller sump pits that require a compact backup solution
  • Situations where a reliable, low-maintenance diaphragm switch minimizes service calls

Installation is straightforward: place the pump in the sump pit with the bottom suction oriented to draw water from the pit floor, connect the discharge line to your existing sump drainage path, and rely on the diaphragm switch to handle cycling. With its durable thermoplastic build and CSA-compliant design, you gain a dependable layer of protection against unexpected water intrusion—so you can sleep a little easier even when the forecast calls for storms.

The Details Specifications

Brand Zoeller
SKU 4014255
UPC 054757100735
Unit 0
Case Pack Quantity 1 per case
Retail Unit Quantity 1
Unit of Measure 0 0
Dimensions (L × W × H) 6 × 14 × 16
Weight 6 lbs
Cubic Feet 0.75286 ft³
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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