Product Overview

The Pentair C-Series Commercial Pump Motor Package | 357208S is a genuine OEM replacement motor package designed for compatible 7.5 HP Pentair C-Series high-performance commercial pool pumps operating on 200/208V, three-phase, 60 Hz electrical service.

Built for demanding commercial aquatic applications, this motor package provides the power required to operate compatible C-Series high-head and medium-head pump wet ends without replacing the complete commercial pump assembly.

The 357208S is commonly used with compatible CHK-75 and CMK-75 C-Series commercial bronze pumps equipped with 7.5 HP, 200/208V, three-phase motors.

This is a dedicated 200/208V motor package. It should not be confused with Pentair 071365S, which is the 7.5 HP three-phase motor package designed for 208-220/440V applications.

Ideal For

• Commercial swimming pools
• Hotels and resorts
• Municipal pools
• Schools and universities
• Aquatic facilities
• Recreation centers
• Competition pools
• HOA and apartment pools
• Large commercial filtration systems
• Pentair C-Series pump motor replacement

Key Features & Benefits

• Genuine Pentair OEM Motor Package – Designed specifically for compatible Pentair C-Series commercial pumps.
• 7.5 HP Commercial Motor – Provides the power required for demanding high-flow circulation applications.
• Three-Phase Design – Intended for commercial three-phase electrical systems.
• Dedicated 200/208V Configuration – Specifically designed for sites using 200/208V power.
• 60 Hz Operation – Correct configuration for standard North American 60 Hz installations.
• Compatible with High- and Medium-Head C-Series Applications – Used with compatible CHK-75 and CMK-75 pump configurations.
• Commercial-Duty Replacement – Allows the existing C-Series wet end to remain in service when the motor requires replacement.
• OEM Fitment – Designed around the shaft, mounting, and hydraulic requirements of the Pentair C-Series platform.
• Single-Speed Motor – Designed for traditional commercial constant-speed circulation applications.

Specifications

Compatible Pentair C-Series Pumps

The 357208S is designed for compatible 7.5 HP C-Series applications using 200/208V three-phase power, including:

CHK-75

7.5 HP – High Head – Three Phase – 200/208V

CMK-75

7.5 HP – Medium Head – Three Phase – 200/208V

The same motor horsepower can be used with different C-Series hydraulic configurations because the impeller and wet end determine whether the pump is high head or medium head.

Always verify the complete pump model before ordering.

High Head vs. Medium Head

The motor package does not determine whether the pump is high head or medium head.

For compatible 7.5 HP C-Series pumps:

CHK-75 – High Head
Uses the applicable high-head impeller configuration.

CMK-75 – Medium Head
Uses the applicable medium-head impeller configuration.

Pentair identifies:

• 073829 – 7.5 HP High Head Impeller
• 070227 – 7.5 HP Medium Head Impeller

Both configurations may use the appropriate 7.5 HP motor package when voltage and phase match.

IMPORTANT – Verify Voltage Before Ordering

Pentair offers several different 7.5 HP C-Series motor packages.

357208S

7.5 HP / Three Phase / 200-208V

071365S

7.5 HP / Three Phase / 208-220/440V

357247S

7.5 HP / Three Phase / 575V

357207S

7.5 HP / Single Phase / 200-208V

357204S

7.5 HP / Single Phase / 230V

These motor packages are not interchangeable simply because they are all rated at 7.5 HP.

Confirm the facility's actual supply voltage and phase before ordering.

200/208V Commercial Applications

Pentair specifically states that 200/208V C-Series applications should use the dedicated 200/208V motor configuration.

Do not assume that a 208-220/440V motor is automatically the correct replacement for an existing 200/208V installation.

For an existing pump originally equipped with 357208S, replacing it with the same OEM motor package helps maintain the intended electrical and pump performance characteristics.

When Should a Commercial Pump Motor Be Replaced?

Common symptoms of motor failure may include:

• Motor does not start
• Breaker or overload repeatedly trips
• Excessive bearing noise
• Motor overheating
• Burnt electrical smell
• Shaft becomes difficult to rotate
• Excessive vibration
• Damaged windings
• Ground fault
• Water intrusion into the motor

Before replacing the motor, the complete pump should be inspected to ensure that another problem—such as a seized impeller, failed bearing, incorrect voltage, phase imbalance, or hydraulic issue—is not responsible for the failure.

Replace the Shaft Seal During Motor Replacement

Whenever a commercial pool pump motor is removed, replacing the mechanical shaft seal is strongly recommended.

Reusing an old shaft seal can allow pool water to leak along the motor shaft and damage the replacement motor.

Technicians should also inspect:

• Mechanical shaft seal
• Water slinger
• Impeller
• Impeller key
• Motor mounting flange
• O-rings
• Pump shaft
• Volute
• Electrical connections

Three-Phase Rotation Check

Three-phase motors can rotate in either direction depending on the incoming phase sequence.

After installation, a qualified technician should briefly verify motor rotation before placing the pump into normal service.

Incorrect rotation can substantially reduce pump performance and may damage equipment if left uncorrected.

Professional Installation Required

This is a 7.5 HP commercial three-phase motor and should be installed by a qualified commercial pool technician or licensed electrician.

Installation should include verification of:

• Supply voltage
• Three-phase electrical service
• Motor rotation
• Proper overcurrent protection
• Motor overload protection
• Grounding
• Bonding
• Shaft seal installation
• Pump alignment and assembly
• Operating amperage

Always disconnect and lock out electrical power before servicing commercial pool equipment.

Frequently Asked Questions

What pumps does Pentair 357208S fit?
It is designed for compatible 7.5 HP Pentair C-Series commercial pumps, commonly including the CHK-75 and CMK-75 200/208V three-phase configurations.

What horsepower is 357208S?
7.5 HP.

Is this single phase or three phase?
Three phase.

What voltage does it require?
It is specifically designed for 200/208V electrical service.

Is this the same as Pentair 071365S?
No. Both are 7.5 HP three-phase C-Series motor packages, but 357208S is 200/208V, while 071365S is listed for 208-220/440V.

Is it a high-head motor?
The motor itself can be used with the appropriate compatible 7.5 HP C-Series hydraulic configuration. The impeller and wet end determine high-head vs. medium-head performance.

What is the high-head 7.5 HP impeller?
Pentair lists 073829 for compatible 7.5 HP high-head C-Series pumps.

What is the medium-head 7.5 HP impeller?
Pentair lists 070227 for compatible 7.5 HP medium-head C-Series pumps.

Should I replace the mechanical seal when changing the motor?
Yes. Installing a new mechanical shaft seal during motor replacement is strongly recommended.

Why Buy From Pool Supply Depot?

Pool Supply Depot supplies genuine Pentair commercial pumps, C-Series motors, impellers, mechanical seals, strainers, filters, heaters, automation systems, and OEM replacement parts for hotels, municipalities, schools, aquatic facilities, pool contractors, and commercial properties nationwide.

Commercial C-Series motors are offered in several voltage and phase configurations. If you're unsure which motor is correct, send us the complete pump model, existing motor label, voltage, and phase before ordering.

Order the Pentair C-Series Commercial Pump Motor Package, 7.5 HP, 200/208V, Three Phase | 357208S from Pool Supply Depot today.