Description
Single-speed electric motor designed for pool pump applications as a replacement motor for WhisperFlo models. It is a 1 HP totally enclosed fan-cooled (TEFC) motor with a 56Y frame intended for mounting in standard pump housings. The motor is suited for residential and light commercial pool circulation where a full-rated single-speed drive is required.
Quick Answer: What Is the Pentair 354821S?
The Pentair 354821S is a pool pump motor: Pentair WhisperFlo Pump Motor, 1 hp, Single-Phase, 115/208 to 230V, 56Y, Square Mount. It is brand new, ships in 1-2 business days, and is backed by the Pentair manufacturer warranty.
Pentair 354821S Specifications
| Brand | Pentair |
|---|---|
| Equipment Type | Pool Pump Motor |
| Model Number | 354821S |
| Frame Size | 56Y |
| Horsepower | 1 hp |
| Voltage | 115/208-230 V |
| Phase | 1 |
| UPC | 788379880347 |
Key Features
- 1 HP single-speed TEFC motor
- 56Y frame for standard pump mounting
- Aluminum fan and anodized motor frame finish
- Large top junction box for easy wiring access
- Improved bearing design for longer life
How It Works
A pool pump motor drives the impeller in the wet end of the pump. Replacement motors let you restore a pump without replacing the housing, strainer and plumbing. Motors are defined by frame (48Y or 56J threaded shaft, square flange or C-face), horsepower, service factor (SF), total horsepower (THP = HP x SF), voltage, speed type and enclosure (ODP or TEFC).
How to Choose the Right Pool Pump Motor
- Match the frame and shaft style exactly: square-flange 56Y vs threaded-shaft 48Y/56J and C-face are not interchangeable.
- Match horsepower and service factor (THP) to the impeller. A motor that is too strong for the impeller can overload; too weak and the pump underperforms.
- Confirm voltage and whether the motor is single speed, two-speed or variable speed.
- Check the DOE replacement motor efficiency rules that apply to dedicated-purpose pool pump motors before ordering.
- Order a seal kit and O-rings with the motor; reuse of the old shaft seal is a common cause of early failure.
If you are replacing an existing part, the fastest way to confirm compatibility is to match the brand and model number on the old equipment. Send us the model number or a photo of the label and our team will help confirm the 354821S is the right fit before you order.
Installation and Safety
Disconnect and lock out power before work. Motor replacement involves line-voltage wiring and bonding, which should be done by a licensed electrician or qualified pool technician following NEC Article 680 and the manufacturer's instructions. Replace the shaft seal whenever the motor and wet end are separated.
Maintenance Tips
- Keep the motor dry and well ventilated; water from a failed seal is the top cause of bearing failure.
- Listen for screeching or grinding that indicates bearing wear.
- Check wiring connections for heat discoloration annually.
- Shade motors from direct sun where possible, without blocking airflow.
What's Included
This listing is for the Pentair 354821S as described in the specifications above. Plumbing, wiring, unions and accessories are not included unless they are listed in the product name or specifications.
Built for Homeowners, Pool Pros and Property Managers
- Homeowners: match your existing model number, then reach out if you want a second set of eyes on compatibility before you order.
- Pool service pros and builders: order quickly, track every shipment, and reorder common parts for your routes and builds.
- Property managers and commercial pools: standardize equipment across properties and plan replacements with help from our team.
White Paper
Frequently Asked Questions About the Pentair 354821S
How do I know which motor I need?
Read the old motor's nameplate: frame, HP, SF, voltage, RPM and shaft type. Match those, or contact our team with the nameplate photo.
Should I replace the motor or the whole pump?
If the wet end, basket and lid are in good condition, a motor replacement is cost-effective. If the housing is cracked or the pump is very old, a complete pump is often the better value.
What is THP?
Total horsepower: rated horsepower multiplied by service factor. Matching THP to the impeller keeps the motor within its design load.
Is this the genuine Pentair part?
Yes. It is brand new Pentair equipment (model 354821S) covered by the manufacturer warranty. Warranty terms vary by product and application; see the manufacturer documentation or ask our team.
