Understanding VS vs. VSF IntelliFlo Drives, Motor Harness Pins, and How to Order the Correct Replacement Motor

Pentair IntelliFlo pumps are some of the most popular variable speed pool pumps on the market, but ordering the correct replacement motor can be confusing. One of the most common mistakes is ordering a Pentair 350305S motor when the pump actually needs a 350105S, or ordering a 350105S when the drive requires the newer 350305S style motor.

The easiest way to tell the difference is to remove the drive from the motor and inspect the motor harness connection underneath the drive.

The key difference is simple:

Pentair Motor	Harness Style	Common Drive Type	Best Way to Identify
350305S	5-pin harness on top of motor	Commonly used with IntelliFlo VSF-style applications	Remove drive and look for 5-pin motor harness
350105S	3-pin harness on top of motor	Commonly used with earlier IntelliFlo VS-style applications	Remove drive and look for 3-pin motor harness

Pool Supply Depot lists the Pentair 350305S as an IntelliFlo VSF pump motor, 3.2 kW, 10-pole replacement motor, while the Pentair 350105S listing identifies it as an IntelliFlo VS pump motor replacement that fits IntelliFlo VF, VS 3050, VS-SVRS, IntelliFloXF, and other compatible IntelliFlo models.

Why This Matters Before Ordering

Pentair IntelliFlo drives and motors do not all use the same communication harness. The motor and drive must match.

If the drive harness and motor harness do not match, the drive will not connect correctly to the motor. That can lead to wasted time, incorrect returns, installation delays, and unnecessary troubleshooting.

Before ordering a replacement motor, you should verify:

The pump model number
The drive type
The motor part number, if still readable
The harness pin count under the drive
Whether the motor has a 3-pin or 5-pin connection

The harness pin count is one of the most useful field checks because labels can be faded, missing, or difficult to read after years of outdoor exposure.

350305S vs. 350105S: What Is the Difference?

Pentair 350305S Motor

The Pentair 350305S is commonly associated with IntelliFlo VSF-style replacement applications. Pool Supply Depot lists the 350305S as a 3.2 kW, 10-pole IntelliFlo VSF pump motor.

This is the motor customers usually need when the pump uses the newer-style drive connection with a 5-pin harness on top of the motor.

Order the Pentair 350305S if:

Your motor has a 5-pin harness on top
Your drive is a VSF-style drive
You are replacing a motor on compatible IntelliFlo VSF-style equipment
Your existing drive plugs into a 5-pin motor connector

Shop Now: Pentair IntelliFlo VSF Pump Motor 3.2 kW 10-Pole | 350305S

Pentair 350105S Motor

The Pentair 350105S is commonly associated with earlier IntelliFlo VS-style replacement applications. Pool Supply Depot lists the 350105S as a 3.2 kW PMSM variable frequency drive motor replacement that fits Pentair IntelliFlo VF, VS 3050, VS-SVRS, IntelliFloXF, IntelliFlo VS, and IntelliFlo i1 variable speed pumps.

This is the motor customers usually need when the pump uses the older-style connection with a 3-pin harness on top of the motor.

Order the Pentair 350105S if:

Your motor has a 3-pin harness on top
Your pump uses an earlier IntelliFlo VS-style drive
Your existing drive plugs into a 3-pin motor connector
You are replacing a motor on a compatible IntelliFlo VS, VF, VS 3050, VS-SVRS, or related IntelliFlo model

Shop Now: Pentair IntelliFlo VS Pump Motor 3.2 kW Replacement Almond | 350105S

The Most Important Rule: Count the Pins Before Ordering

If you are not sure which IntelliFlo motor you need, do not guess.

Remove the drive and look at the harness connection on the top of the motor.

If the motor has 5 pins:

You most likely need the Pentair 350305S motor.

If the motor has 3 pins:

You most likely need the Pentair 350105S motor.

This quick inspection can prevent ordering the wrong motor.

How to Remove the IntelliFlo Drive to Check the Motor Harness

Before beginning, remember that pool pump motors and drives involve high voltage. If you are not comfortable working around electrical equipment, contact a licensed pool professional or electrician.

Pentair’s drive replacement instructions warn users to turn off all electrical breakers and switches before servicing and to avoid touching the electrical contacts on the underside of the drive assembly.

Tools You May Need

Phillips screwdriver or nut driver, depending on model
Camera or phone
Flashlight
Clean towel or small container for screws
Safety gloves
Multimeter, if qualified to verify power is off

Step 1: Turn Off Power at the Breaker

Turn off the pool pump at the breaker. Do not rely only on the keypad or automation system.

The IntelliFlo pump must be completely de-energized before removing the drive. Pentair’s installation guidance for IntelliFlo motors states that all electrical breakers and switches should be turned off before wiring or servicing the motor.

Step 2: Confirm the Pump Is Off

Make sure the pump display is off and the pump cannot start from automation.

If the pump is connected to automation, disable pump schedules or place the system in service mode before working.

Step 3: Remove the Drive Cover or Drive Assembly Screws

On most IntelliFlo-style pumps, the drive is mounted on top of the motor. Remove the screws holding the drive or keypad/drive assembly in place.

Keep the screws in a safe place so they do not fall into the equipment pad.

Step 4: Carefully Lift the Drive Straight Up

Lift the drive carefully. Do not yank or twist it.

There is a harness connection underneath the drive that plugs into the top of the motor. The goal is to expose that connection so you can identify whether the motor is the 3-pin or 5-pin style.

Pentair warns to avoid touching the electrical contacts on the underside of the drive assembly during removal.

Step 5: Inspect the Harness on Top of the Motor

Look at the connector on top of the motor.

You are looking for the number of pins in the harness connection:

3 pins = 350105S style motor
5 pins = 350305S style motor

Take a clear photo of the harness before ordering. This is helpful if you need assistance confirming the correct replacement part.

Step 6: Check the Motor Label

If the motor label is still readable, look for the existing motor part number, voltage, and model information.

Common clues include:

Existing motor part number
Pump model number
Pump serial number
Voltage rating
Motor kW rating
Drive model information

Do not rely only on the pump lid or housing label. Pumps are often repaired over time, and drives or motors may have been replaced before.

Step 7: Match the Motor to the Drive

After identifying the harness pin count, match the motor to the drive:

What You See Under the Drive	Correct Motor to Order
5-pin motor harness	Pentair 350305S
3-pin motor harness	Pentair 350105S

If the drive has already been replaced before, the harness inspection is usually more reliable than guessing based only on the original pump model.

How to Tell If You Have a VS or VSF IntelliFlo Drive

The terms VS and VSF can also help identify the correct motor, but the harness is still the best field check.

IntelliFlo VS

“VS” stands for Variable Speed. These pumps are programmed by RPM speeds. Earlier IntelliFlo VS-style pumps are commonly associated with the 3-pin / 350105S motor style.

IntelliFlo VSF

“VSF” stands for Variable Speed and Flow. These pumps can operate by speed and flow-based control depending on setup. VSF-style applications are commonly associated with the 5-pin / 350305S motor style.

A rebuilt VSF drive listing from Pool Supply Depot specifically notes that it works with Pentair 5-pin motors 350305S and compatible IntelliFlo VSF pump models such as IntelliFlo VSF 011056, IntelliFloXF VSF 022056, Sta-Rite IntelliPro VSF 023055, and Sta-Rite IntelliProXF VSF 023056.

Common Mistakes When Ordering IntelliFlo Motors

Mistake 1: Ordering by Horsepower Only

Both motors may be described around the same 3.2 kW power class, but that does not mean they use the same drive connection.

Always check the harness.

Mistake 2: Assuming All IntelliFlo Motors Are the Same

IntelliFlo pumps have gone through multiple versions. A motor from one IntelliFlo pump may not match the drive from another.

Mistake 3: Ordering a Motor Without Removing the Drive

The correct connector may not be visible until the drive is removed.

Removing the drive and counting the pins is the fastest way to avoid the wrong part.

Mistake 4: Replacing the Motor When the Drive Is the Problem

A failed pump can be caused by the motor, drive, keypad, wiring, automation, or incoming power.

Before replacing the motor, consider the symptoms:

Symptom	Possible Cause
Display dead	Breaker, power, drive, keypad
Drive powers on but motor will not spin	Motor, drive, wiring, internal fault
Drive error code	Drive, motor, communication issue, voltage issue
Loud bearing noise	Motor bearing failure
Pump trips breaker	Motor winding, drive failure, water intrusion, electrical issue

If the motor is noisy or seized, the motor is likely the issue. If the display is dead or the pump has electronic fault codes, the drive may also need to be inspected.

Should You Replace the Drive and Motor Together?

Sometimes replacing only the motor is enough. Other times, the drive and motor may both be damaged.

You may want to inspect or replace the drive if:

The keypad/display is not working
There are burn marks or water damage
The drive has visible corrosion
The pump has communication errors
The drive will not power up
The drive does not match the replacement motor harness

Pool Supply Depot carries drive options, including rebuilt VSF drive options for compatible 5-pin motor applications and drive kits for IntelliFlo/IntelliPro VSF applications.

Recommended Ordering Checklist

Before ordering a Pentair IntelliFlo replacement motor, collect this information:

Take a photo of the complete pump
Take a photo of the pump label
Take a photo of the drive label
Remove the drive and take a photo of the motor harness
Count the pins: 3-pin or 5-pin
Confirm whether your drive is VS or VSF
Match the motor to the harness
Order the correct replacement motor

Shop Pentair IntelliFlo Replacement Motors

Motor	Harness Style	Best Match	Purchase Link
Pentair 350305S IntelliFlo VSF Pump Motor, 3.2 kW 10-Pole	5-pin	VSF-style IntelliFlo applications	Shop Pentair 350305S
Pentair 350105S IntelliFlo VS Pump Motor, 3.2 kW Replacement Almond	3-pin	VS-style IntelliFlo applications	Shop Pentair 350105S

Final Recommendation

If you are replacing a Pentair IntelliFlo motor, the most important step is to remove the drive and inspect the harness on top of the motor.

If your motor has a 5-pin harness, order the Pentair 350305S.

If your motor has a 3-pin harness, order the Pentair 350105S.

Do not order based only on horsepower, pump color, or the word “IntelliFlo.” The correct motor depends on the drive style and motor harness connection.

For the safest result, take photos of the pump label, drive label, and harness connection before ordering. If you are unsure, send the photos to Pool Supply Depot so the correct replacement motor can be confirmed before purchase.

Customer-Facing FAQ

How do I know if I need a Pentair 350305S or 350105S motor?

Remove the drive from the top of the pump motor and inspect the harness connection. A 5-pin harness usually indicates the 350305S motor. A 3-pin harness usually indicates the 350105S motor.

What is the difference between a Pentair VS and VSF drive?

A VS drive controls pump speed by RPM. A VSF drive can control both variable speed and variable flow depending on the pump model and setup. In the field, the most useful check is the motor harness pin count.

Can I order the motor by horsepower only?

No. Horsepower or kW rating alone is not enough. You must confirm the motor harness and drive compatibility.

Do I need to remove the drive to identify the motor?

Yes, in many cases. The harness connection is located under the drive, so removing the drive is the best way to confirm whether the motor has a 3-pin or 5-pin connector.

Is this a DIY repair?

Some experienced pool professionals and electricians can perform this repair, but IntelliFlo pumps use high voltage. If you are not trained or comfortable with electrical service, have a qualified professional inspect and replace the motor.

Should I replace the motor or the drive?

That depends on the symptoms. Noisy bearings, seized rotation, or motor failure symptoms may point to the motor. A dead display, keypad failure, communication fault, or visible drive damage may point to the drive. In some cases, both parts should be inspected before replacing anything.