
OUTDOOR / ROOFTOP Water Booster Pumps
Designed for outdoor use in warm climate areas
Compact, powerful, and engineered for performance
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Outdoor / Rooftop Water Booster Pump
Product Overview:
The TW1111 Series booster pump system is engineered specifically for outdoor applications in warm climate regions. Constructed with stainless steel centrifugal pumps and mounted on a rugged, powder-coated 12-gauge steel strut, this system is designed for durability and structural integrity. Each unit includes NEMA 4X-rated variable frequency drives, offering reliable protection against rain and sun exposure (note: not rated for freezing conditions).
Available Models
Choose the model that best suits your needs and press Add to Quote to request pricing. For Model Specifications, scroll down to Submittals below.
GPM And Boost MAX PER PUMP
| Select | Model | HP | Common Design Points | Submittal |
|---|---|---|---|---|
| TW1111-2T-3K | 1/2 HP | 15 GPM @ 45 PSI Boost | Not Available | |
| TW1111-2T-4K | 1/2 HP | 15 GPM @ 60 PSI Boost | Not Available | |
| TW1111-2T-5K | 3/4 HP | 15 GPM @ 70 PSI Boost | Not Available | |
| TW1111-2T-6K | 3/4 HP | 15 GPM @ 80 PSI Boost | Not Available | |
| TW1111-4T-3K | 3/4 HP | 35 GPM @ 40 PSI Boost | Not Available | |
| TW1111-4T-4K | 1 HP | 36 GPM @ 60 PSI Boost | Not Available | |
| TW1111-4T-5K | 1.5 HP | 36 GPM @ 70 PSI Boost | Not Available | |
| TW1111-4T-6K | 2 HP | 36 GPM @ 100 PSI Boost | Not Available | |
| TW1111-8T-2.5K | 1 HP | 50 GPM @ 35 PSI Boost | Not Available | |
| TW1111-8T-2K | 3/4 HP | 50 GPM @ 30 PSI Boost | Not Available |
Common design points are examples of typlical applications. Actual performance depends on incoming pressure,
desired set pressure, flow requirements, piping conditions, and system demand.
Not sure which Outdoor / Rooftop Water Booster Pump is right for your application?
If you do not see what you are looking for, additional models and custom configurations are
available to meet your needs.
TW1111 Series – Built for Outdoor Performance in Warm Climates
Data centers require precision — and that's exactly what our booster systems deliver. Downtime isn’t an option — and poor water flow can lead to thermal shutdowns or degraded server performance. With Towle-Whitney’s data center pump solutions, you’re protected by a system designed to keep cooling operations running smoothly, regardless of demand spikes or equipment cycling.
- High-Performance Pumps: Utilizes cast iron and stainless steel centrifugal pumps for durability and efficiency.
- Variable Frequency Drives (VFDs): Equipped with UL508-rated VFDs that adjust pump operation to maintain constant pressure, optimizing energy consumption.
- Modular Design: Built on a painted steel frame that allows for easy transportation and installation, even in tight spaces.
- Lead-Lag Operation: Programmable VFDs alternate lead pumps every 24 hours, ensuring even wear and extended system life.
- Plug-and-Play Installation: Systems come pre-wired and factory-tested, reducing on-site labor and commissioning time.
- Expansion Tank Included: Each system includes a properly sized expansion tank to accommodate system pressure changes.
| Specification Sheets (Submittals) | |
|---|---|
| Model | TW1111-20R-40.pdf |
| Model | TW1111-10R-65.pdf |
| Model | TW1111-15R-40.pdf |
| Model | TW1111-15R-50.pdf |
| Model | TW1111-15R-60.pdf |
In an effort to provide the highest level of customer service we offer a limited three warranty on all of these water booster pump models. All of the model specific data sheets have a page dedicated to discussing the warranty, but don’t hesitate to reach out with additional questions.

| Specifications | |
|---|---|
| HP | 7.5 - 15 |
| GPM | 100 - 360 |
| PSI Boost | 85 - 100 |
About the Outdoor / Rooftop Water Booster Pump Series
TW1111 Outdoor / Rooftop Water Booster Pump systems are designed to provide dependable, efficient pressure boosting with factory-built controls, compact installation, and simplified service.
Lead, Lag, and Alternate Operation
Prewired and Factory Tested
UL508 Rated VFDs
Modular Frame for Easy Installation
Plug-and-Play Installation
BACnet, Modbus, and EtherNet/IP Options
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