Pentair WhisperFlo VST

If you own a WhisperFlo in the upper half of the old WFE range and it is failing, this is the pump Pentair points you at. Its own description is unambiguous: a superior, drop-in replacement for existing Pentair WhisperFlo pumps.

That matters because the single-speed WhisperFlo no longer goes there. The DOE rules took that range down to one 1.1 total horsepower model, so a dying WFE-8 or WFE-12 has no like-for-like successor. This is the successor.

Two point six total horsepower, honestly labeled

Worth stating because it is not always true on a pump:

• Total horsepower 2.6
• Service factor 1.0
• Hydraulic horsepower 1.64
• WEF 8.4

A service factor of 1.0 means the nameplate is the whole story — there is no multiplier folded in, which is the trap the LA01N illustrates, where a pump sold as ¾ HP is documented at 1.13 total. Here 2.6 is 2.6.

The hydraulic horsepower figure is the one the regulations actually use, and at 1.64 HHP this pump is well above the 0.711 threshold where variable speed stops being optional. That is why there is no single-speed version of it.

Its smaller sibling is worth knowing for comparison: the SuperFlo VST at 2.2 THP and WEF 9.0. Note which way that goes — the smaller pump is the more efficient one by the DOE's own measure, so more horsepower is not a free upgrade. Work out the flow you actually need before assuming the bigger number is better.

Three speeds, not eight

This is the real difference between the VST and Pentair's flagship, and it is a genuine trade rather than a defect.

The VST gives you three programmable speeds plus a Quick Clean override, set on an onboard digital display with a real 24-hour clock. When more than one input is active the priority runs Quick Clean, then Speed 3, then Speed 2, then Speed 1.

Three speeds covers the ordinary case comfortably: a filtration speed, a higher speed for a cleaner or a feature, and a top speed for priming or vacuuming. If you need finer control than that, or flow-based rather than speed-based control, the IntelliFlo3 VSF is the pump that does it.

The speed range is 450 to 3450 RPM. That 450 RPM floor is lower than most — the Jandy VS FloPro stops at 600 — and the floor is where a variable-speed pump earns its money, because power falls much faster than speed.

The factory schedule runs longer than the pump it is compared to

The most useful thing on this page, and it is in the manual rather than the brochure.

Out of the box, the VST runs this schedule:

• Speed 1 — 3000 RPM for 2 hours, starting at 8:00am
• Speed 2 — 1400 RPM for 10 hours, immediately after
• Speed 3 — 2200 RPM for 2 hours, immediately after that
• Then stationary for 10 hours, restarting at 8:00am

That is fourteen hours of running a day, four of them at 2200 RPM or above.

Now set it beside Pentair's savings claim, which is up to 90 percent against a single-speed pump — measured, per the footnote, against one running 12 hours per day at $0.16 per kilowatt-hour in a 20,000 gallon pool.

So a VST left on its factory schedule runs two hours longer than the baseline it is being compared against, and spends four of those hours at speeds where a variable-speed pump saves very little. The 90 percent is available and it is not automatic. It is the reward for programming the pump for your pool, and the default schedule is a starting point rather than a recommendation.

Set Speed 2 to the lowest speed that keeps the water sanitary and give it the hours, and cut Speeds 1 and 3 back to what your cleaner or spa jets actually need. The running cost calculator takes your own hours and rate.

One practical note from the same section: the drive keeps its clock through a power outage for 24 hours. Longer than that and the clock has to be reset, which on a pump whose whole schedule hangs off the time of day is worth checking after a storm.

Dual voltage that genuinely needs no wiring change

Pentair's phrasing is stronger than most and the specification backs it: the pump adapts to 115 V through 230 V and 50 or 60 Hz power with no special wiring or switching.

That is a real difference from how other pumps handle it. The Jandy VS FloPro runs on either supply but the wiring compartment has to be changed over, and its larger models need a 30 amp breaker to do it. This one takes what it is given:

• 115 V — 13.9 amps
• 208 to 230 V — 11.1 down to 10.1 amps

The 50 Hz support is unusual on a residential pool pump and matters only if you are outside North America, but the no-switching part matters everywhere. On a retrofit where the existing circuit is 115 V, this pump goes on it without an electrician changing anything inside the drive.

Buying it online costs you the labor

The pump comes with two part numbers and they are the same machine:

• 011533 — through a dealer
• EC-011533 — approved for online sale

Pentair's warranty page sets out three warranty types, and the difference is not the term:

• Bundle warranty — three years, for multiple products bought together
• Standard warranty — one year minimum, parts and labor
• E-commerce warranty — one year minimum, parts only

And in the labor note, stated directly: labor is not covered for internet purchases.

On a 45 pound pump that Pentair requires to be professionally installed, labor is a real share of any warranty claim. That is the cost of the cheaper price, and it is worth pricing rather than assuming.

Two other clauses on that page apply here. Consumables carry one year of parts and labor regardless of any bundle — and Pentair's list of consumables includes pump mechanical seals, which is the part most likely to need a warranty claim on any pump. And the warranty starts on the date of installation, not the date of purchase, which is in your favor if the pump sits in a garage over winter.

The parts list is in the guide

Pentair's 2021 pool pump parts catalog had no section for the WhisperFlo VST, but its installation and user's guide has everything: an exploded view on page 21 with 31 numbered parts, two alternatives at item 2 and item 16, and four assemblies and kits that aren't drawn. The guide covers both the WhisperFlo VS and the WhisperFlo VST.

The wet end is the WhisperFlo's. Every number from the lid clamp back to the impeller also appears on the WhisperFlo's parts list: the lid, basket and lid o-ring, the strainer pot, the diffuser, the seal plate kit and the impeller. Some fastener descriptions differ slightly between the two documents, and the VST guide prints several numbers with a trailing z or s where the WhisperFlo sheet doesn't. What's the VST's own is the back end: the drive cover (356279), drive kit (356282), motor (356286s), motor/drive assembly (356289s) and motor fan guard kit (357923z).

Pentair's 2025-2026 catalog now has a WhisperFlo VST section, on page 437, with US list prices, and it changes the back end. It lists the drive kit as 358211, not 356282. Its drive cover row gives no number of its own. It says to order 358211 for a pump built before May 2025 and 358215 from May 2025, but 358211 is the drive kit's number. The same row appears in the catalog's SuperMax VS and SuperFlo table. Ask a dealer before ordering a drive cover.

Two alternatives are worth knowing. The lid comes clear (357151) or chemical resistant (357156). And the shaft seal comes as the standard PA-7 with a ceramic seat (071734s) or an ozone and salt resistant version (071732s), which is the one to ask for on a salt pool or a system with ozone.

For bigger jobs Pentair sells the wet end in stages: the seal plate kit (350202) with the seal already fitted, the strainer pot assembly (357243), the strainer pot and seal plate kit (357149), and the fluid assembly (075455), which is everything except the motor and drive.