Pentair SuperFlo VS and VST

If you are replacing a Hayward Super Pump, this is the pump the quote will most likely name — and that is not an accident. Pentair markets the SuperFlo VST as a drop-in replacement for the Super Pump and for older SuperFlo pumps, which is unusually direct language from a manufacturer about a competitor's machine.

Check the port size before anything else

The SuperFlo runs 1.5-inch ports. The Hayward Super Pump runs 2-inch, and so does the WhisperFlo.

"Drop-in" refers to the footprint and the plumbing height, not the pipe. On a pool plumbed in 2-inch pipe you are adding adapters at both ports, and 1.5-inch is a real restriction — pipe diameter caps your safe flow regardless of what the pump can do.

On a pool already plumbed in 1.5-inch, none of that matters and the swap genuinely is straightforward. Measure first.

The replacement runs the other way too. Hayward's replacement guide for its OmniX pumps maps the single-speed SuperFlo models and the SuperFlo VS to its MaxFlo VS 400, which plumbs in with 2 x 2 1/2-inch unions, so the same pipe check applies in reverse.

Which one you have

SuperFlo VS, part number 342001, is discontinued. Pentair names the VST as its replacement and still lists parts for it, so a working VS is not a problem to own.

There is a third number worth recognizing: EC-342001. The EC prefix is Pentair's online-sale trim, the same idea as the W3 prefix Hayward uses, and it is what you will usually find listed on a marketplace rather than at a dealer.

SuperFlo VST, 342002, is the current pump. It adds RS-485 so it can talk to automation, a revised mechanical seal, and a keypad with three programmable speeds and a real-time clock. Two Pentair guides disagree about whether its smallest controller, the IntelliConnect, can use that RS-485, and its page sets out both.

A black pump of the same shape with a Sta-Rite badge is the SuperMax VS, 343001. It shares this pump's installation guide and parts list, and ENERGY STAR's test results for it match the VST's figure for figure.

Both are rated the same on paper: 2.2 total horsepower, a hydraulic horsepower of 1.08, and a WEF of 9.0 — second only to the 1.5 HP IntelliFlo3 at 9.4 among the Pentair pumps on this site, and comfortably ahead of every larger one. Efficiency and size are different questions, and they mostly run in opposite directions.

The 9.0 assumes you wire it on 230V

This is the fact most likely to cost you money on this pump, and it is one line on Pentair's own page.

The SuperFlo runs on 115V or 230V with no switch to set — the drive works it out. But the efficiency rating does not survive the choice. Pentair states WEF 9.0 at 230V and WEF 7.3 at 115V: the same pump, the same schedule, about a fifth less efficient on the lower voltage.

It matters because 115V is the easy option. An old single-speed pump on a 115V circuit invites a like-for-like swap, and the pump will run perfectly well that way. But the whole argument for buying a variable-speed pump is the electricity bill, and running it on 115V gives away a meaningful slice of the saving that justified the price. If the pad can be brought to 230V, that is the version to buy.

It also affects any rebate tied to a WEF threshold, since 7.3 and 9.0 do not clear the same bars.

A note on where those numbers come from, because Pentair has printed several. The 9.0 and 7.3 pair is from the product pages for both the VS and the VST. The shared installation manual gives a bare 9.1 without saying which voltage it applies to. The SuperFlo VS manual gives 7.3 at 115V but 6.6 at 230V, which would make the lower voltage the more efficient one — the opposite of every other document, and of how the pump works. ENERGY STAR's listing, the one tied to the pump's certification, gives the VST 8.6, with no voltage attached. Where Pentair's documents disagree the product pages are the figures to use.

There are two build dates, not one, and they split different halves of the pump

This is the most expensive thing to get wrong on this page, so it is worth reading before you order anything.

Pentair's manual prints two parts diagrams, one for pumps built before 15 October 2020 and one for pumps built after. That split is the drive end: drive cover, drive kit, motor and motor-drive assembly all change, the newer list adds RS-485 and TEFC variants, and the digital input wiring kit (353129Z) gives way to the RS-485 automation kit (356324Z).

Inside the earlier diagram there is a second split, in mid-June 2019, and it is the one people miss because it is set in small type inside the table rather than in a heading. That one is the wet end. Five parts changed:

• Impeller — 355074 became C105-238PDCA
• Diffuser — 355618 became 355949
• Diffuser seal — 355030 became 355331
• Seal plate — 356012 became 356071 in almond, 355612 became 356072 in black
• Shaft seal — seal set 354545S became 17351-0101S

"Mid-June" rather than a date because Pentair's two manuals do not agree on the day. The combined SuperFlo VST / VS / SuperMax manual says 17 June 2019. The SuperFlo VS manual — which carries a later revision date, so it is not simply the older document — says 10 June. Same five parts, same ten numbers, one week apart. If your pump was built in June 2019, do not order on the date. Open it and read the number off the part.

So the rule is not "wet end safe, drive end risky". Both halves changed, at different times. Order nothing but the strainer pot side on a part number alone. The pot, lid, lid o-ring, basket, locking ring, base, drain plugs and unions have carried through unchanged, and everything from the seal plate inward has not.

Pentair does not say in the manual where to read the build date off the pump, which is unhelpful given that both diagrams hang on it. The practical route is to open the pump and read the number off the part you are replacing before you order its twin, or to give the serial number to Pentair or a dealer and have them tell you which diagram applies.

Pentair's 2025-2026 catalog moves the drive end on again. For pumps built after October 2020 it lists new drive kits, 358211 in almond and 358212 in black. For earlier pumps it lists no drive cover, drive kit or motor, only the complete motor and drive assembly, 358204Z or 358205Z. Its drive cover rows, which split again at May 2025, contradict each other, so ask a dealer before ordering a cover. The SuperMax VS page, for the black Sta-Rite version of this pump, sets out the new numbers with their list prices.

One caution about parts sheets. The single-page SuperFlo VS parts sheet still in circulation lists the pre-2019 wet end with no dates on it at all, and its impeller number, 355086, appears in neither manual. Where a parts sheet and a manual disagree, go with the manual.

What a failing impeller looks like here

There is one impeller regardless of the speed you run — unlike the single-speed pumps, where it changes with horsepower — because a variable-speed pump trims its output with the drive instead.

The SuperFlo holds the speed you set, not a flow. Pentair's pump family brochure draws the line: a VSF pump adjusts its speed to maintain flow, and a VS pump runs at the speeds you set. So a worn or blocked impeller shows up the ordinary way, as weaker returns at the same RPM. Pentair's troubleshooting chart puts a clogged impeller under reduced flow, and a loose one under a pump that runs with no flow at all. A repeated 02 fault, power module over current, also sends you to the impeller and shaft seal.

Noting how the returns look at your usual speed and run time while the pump is healthy gives you something to compare against later.