American Whirlpool · PowerPool

American Whirlpool MB4

14′ long
Jet current
One temperature
9 seats

American Whirlpool MB4 swim spa from above, showing the lane and seats

Photography © American Whirlpool, shown for identification

Price on request

No manufacturer pays us. How we make money

Updated September 2026By the HotTubFinder research desk

Room to swim. The lane, and the current you swim against.

How tall are you?

Outside of the cabinet: 14′
Open water to swim in: Not published
You, arms overhead: 7′

The maker doesn't publish the open water on the MB4. Seats, steps and the current housing take their share of the 14′, so ask the dealer for it.

2 swim jets
The same pumps also feed the seats, so current and massage share the power.
How currents compare →
One zone, one temperature
Lap swimmers like 78 to 82°F and a hot tub runs 100 to 104, so you pick a compromise or change the setting and wait.
Is dual temperature worth it →
47″ deep inside
At the dealer, stand where you’d swim and ask where the water line would come on you.

How much room a swimmer needs

What it costs. To buy, and to keep warm.

The swim spa: Price on requestGet the price range →
Keeping it warm: About $65 a month with the cover on, from its California listing. More in a cold climate and when you swim a lot.
On top: A concrete pad, a dedicated circuit, delivery and sometimes a crane. What those cost

Energy detail

Cost to leave it on

California listing

Watts it draws just holding temperature with the cover on, as filed with the state of California. Listed at California's standby limit for its size.

0 WLimit 492 W

This model: 491 W
California’s limit for its volume: 492 W
At that rate for a year: About 4,300 kWh
Filed as: MB4 · listed 2020 · cover MB4-4/3

Source California Energy Commission appliance database ↗What decides running cost →

What owners say. About American Whirlpool swim spas.

What they complain about

Weeks-long wait for a part on an older MAAX swim spa
One owner of a MAAX swim spa more than ten years old complained that a leaking pump union left the spa waiting several weeks because the dealer had to order the part from the East Coast. MAAX replied that parts ship within two weeks, that the local dealer does the repair, and offered its customer care line to speed things up. It's a single complaint about an older MAAX-branded spa, and we could read it only through a search engine's summary of the BBB page.

Everything owners report about American Whirlpool

How it’s built. In plain words.

Warranty: 5-year structure warranty. 5 years short of the 10-year median across the 161 swim spas that publish one. First owner only.
Frame and shellYes: Galvanized steel frame and ABS bottom pan on every model; the frame is warranted for life. Why it matters
Getting at the equipmentYes: No foam to dig through and ordinary pumps, but the spa must stay reachable on all four sides. Why it matters
Cover and lifterNot published: American Whirlpool doesn't publish this. Ask the dealer. Why it matters

These findings cover the American Whirlpool swim spa line; each names the models it applies to.

The details

Every specification48 figures, each linked to where we read it

Outside size: 14′ × 7′ 6″; 50" tall
Open swim length: Not published; Ask the dealer
Current: Jets; MAAX Force · 2 jets
Swim pumps: Not published
Water: 1,325 gal; 47" deep
Weight: 13,000 lb; Full
Electrical: 240V / 50A; One circuit · 60A recommended
Seats: 9; One temperature

Size

Length: 168" (14′)
Width: 90" (7′ 6″)
Height: 50"
Depth: 47"
Open swim length: Not published

Swim current

Current type: Jets
Current system: MAAX Force
Driven by: Pump
Swim jets: 2
Swim pumps only run the current: No
Current width: 30"

Zones and seating

Dual zone: No
Dual temperature: No
Seats: 9

Water and weight

Water capacity: 1,325 gal
Dry weight: 2,000 lb
Filled weight: 13,000 lb

Therapy jets

Jets: 27

Heat and water care

Controls: Gecko in.k1000 keypad (POWERWORKS® control system)
App or Wi-Fi: Optional
Heater: Not published

Electrical

Voltage: 240 V
Minimum breaker: 50 A
Recommended breaker: 60 A
Circuits needed: 1
Total amperage: 50 A

Construction

Shell backing: Fiberglass vessel structure
Frame: Galvanized steel
Base: ABS pan
Insulation: Perimeter
In-ground install allowed: Yes

Doesn’t have: circulation pump.

Speed control · Variable, fully adjustable jet stream; two-speed pumps; swim training drills on the…

Variable, fully adjustable jet stream; two-speed pumps; swim training drills on the in.k1000 panel

Electrical notes · GFCI-protected dedicated 240 V, 60 Hz, single-phase, 4-wire sub-feed wired by a licensed…

GFCI-protected dedicated 240 V, 60 Hz, single-phase, 4-wire sub-feed wired by a licensed electrician; copper conductors only. The manual gives two heater rules. Rule 1: the heater stays on only while no more than two pumps run on high speed. Rule 2: the heater stays on only with Pump 1 on low speed, and only the spa light can run without turning the heater off. Under either rule, all pumps run on high when the heater is off.

Cover · WeatherShield foam-insulated cover with tie-downs; maker describes its covers as…

WeatherShield foam-insulated cover with tie-downs; maker describes its covers as copper-lined with removable heat-sealing pillows

Where American Whirlpool’s own figures disagree (3) · seats, dry weight, filled weight

American Whirlpool’s own documents give two answers. Check yours against the quote before you sign.

Seats

americanwhirlpool.com ↗

bullgrillsandspas.com ↗

Dry weight

2,000 lb

americanwhirlpool.com ↗

2,100 lb

bullgrillsandspas.com ↗

Filled weight

13,000 lb

americanwhirlpool.com ↗

12,950 lb

bullgrillsandspas.com ↗

Where these figures come from (6 American Whirlpool documents)

American Whirlpool on the ten things we checkCurrent, room, frame, site, running cost, service, warranty and more

Ten things that decide whether a swim spa works for you and lasts, answered for American Whirlpool’s swim spas. Tap any for the detail.

Swim currentJets, not a propeller: 2-3 MAAX Force jets on the M models and DM8, 2-4 'Turbo'…Partly

The MB4, ML4, MX5, MX6 and DM8 use MAAX Force jets, which the maker says make a smooth, variable stream about 30 inches wide. The RB4, RL4 and RF2 use four 'Turbo' or 'Power' swim jets and the RL5 two unnamed jets, with no width published. Air can be added through air controls, and the manual says to close them while swimming; no flow figure or number of speed steps is published.

Applies to: All nine models; MAAX Force on DM8, MB4, ML4, MX5 and MX6 only.

What this means, and how to check it →americanwhirlpool.com ↗bullgrillsandspas.com ↗

Room to swimDepth is published (46 to 56 in); American Whirlpool doesn't publish the open swim…Partly

Outside lengths run from 146 inches (RF2) to 218 inches (DM8), and each page lists a 'Depth' of 46 to 56 inches, deepest on the 60-inch-tall MX5, MX6 and RL5, without saying whether that's water depth. How much of each spa is open lane between the jets and the seats isn't stated; on the DM8 the separate hot tub end takes part of the 18 feet.

Applies to: All nine models.

What this means, and how to check it →americanwhirlpool.com ↗americanwhirlpool.com ↗

Frame and shellGalvanized steel frame and ABS bottom pan on every model; the frame is warranted…Yes

Every product page lists a steel sub-structure, the PowerPool warranty card calls it a zinc-coated steel structural support system with a lifetime warranty, and the brochure says every PowerPool has an ABS bottom pan. The shell itself, which the card calls a 'fiberglass vessel structure', is warranted only 5 years against water loss, and no steel gauge is published.

Applies to: All nine models.

What this means, and how to check it →res.cloudinary.com ↗bullgrillsandspas.com ↗

Site prepCrane placement, a concrete pad 12 inches bigger than the spa all round, and a…Partly

The manual recommends setting a swim spa by crane with an 8-foot spreader bar, on a concrete pad at least 12 inches wider and longer than the spa, with the whole frame perimeter evenly supported; the product pages list full weights of 10,955 to 19,730 lb (the 2025 brochure gives the MX5 19,930). It gives no pad thickness or reinforcement, and the warranty treats an uneven or insufficient foundation as abuse. Minimum breakers run from 30 A (RL5) to 60 A (MX5, MX6), and the DM8 needs separate supplies for each end.

Applies to: All nine models.

What this means, and how to check it →americanwhirlpool.com ↗americanwhirlpool.com ↗

Running costPasses California's standby limit on every model, but only by 1 wattPartly

Northern Exposure lines the cabinet walls, floor and cover with copper-backed recycled fiber and Thinsulate instead of filling it with foam, and the maker publishes no R-value. Every American Whirlpool swim spa's California listing sits exactly 1 W under its limit (the RL4 at 541 of 542 W), and no heat pump is listed for any model. The manual warns the water can drift above its set temperature in warm weather ('thermal creep'), which it puts down to the heat-capturing design, and says a swim spa takes 18 to 24 hours to heat up at first on a 230 V hookup.

Applies to: All nine models; the DM8's listed figure covers its spa end only.

What this means, and how to check it →cacertappliances.energy.ca.gov ↗americanwhirlpool.com ↗

Dual zoneOnly the DM8: an 18-foot swim spa with a walled-off 5-seat hot tub that's…Yes

The DM8 splits 1,950 gallons into a 1,650-gallon swim end with 3 seats and a 300-gallon, 5-seat spa end with its own pump. The maker says the hot tub end is controlled separately, and each end needs its own 240 V supply. The other eight models are one body of water with 3 to 9 seats.

Applies to: DM8 only.

What this means, and how to check it →americanwhirlpool.com ↗bullgrillsandspas.com ↗

Service accessNo foam to dig through and ordinary pumps, but the spa must stay reachable on all…Yes

Northern Exposure lines the cabinet instead of filling it, and the maker's construction page says that lets its hot tubs and spas be serviced back to factory specifications in your yard; the brochure says PowerPools are built to the same standards as its hot tubs. The current runs on standard 56-frame pumps rather than a hydraulic drive. The manual requires service access on all four sides and a drained, accessible vault for below-grade installs, and the warranty requires every side panel to come off without obstruction.

Applies to: All nine models.

What this means, and how to check it →americanwhirlpool.com ↗americanwhirlpool.com ↗

Warranty termsLifetime on the steel frame, but only 5 years on the shell, surface, equipment and…Partly

The PowerPool/xStream card gives the zinc-coated frame a lifetime warranty; 5 years on vessel structure (water loss only), surface, equipment, plumbing and labor; 2 years on side panels and jet inserts; and 90 days on headrests and diverter valves. It ends if the spa is sold, excludes the cover, lets the servicer bill travel and reasonable labor, and leaves removal and reinstallation of a replacement spa to you. American Whirlpool publishes no terms itself; the card (Rev 05/2018) is posted on MAAX's Vita Spa site.

Applies to: All nine models (card covers the PowerPool line generally).

What this means, and how to check it →res.cloudinary.com ↗vitaspa.com ↗

Cover and lifterAmerican Whirlpool doesn't publish this. Ask the dealerNot published

The brochure mentions a locking insulated cover and the manual a foam-insulated WeatherShield cover with tie-downs, but no page says whether a cover or lifter comes with the spa, and the warranty excludes the cover. California's listings name a model-specific tested cover (for example RL4-4/3), which is the one to ask for.

Applies to: All nine models.

What this means, and how to check it →americanwhirlpool.com ↗americanwhirlpool.com ↗

Service and originServiced only through dealers, with no public dealer list; trade press reported in…Partly

Warranty work goes through an authorized MAAX Spas dealer or servicer, and MAAX must pre-authorize in-field service where there's no dealer; the maker's 'Find a Store' page is a contact form, not a list. The maker doesn't say where the swim spas are built. Trade press reported in 2021 that a new swim-spa-only plant in Ottumwa, Iowa would build the PowerPool line, with hot tubs staying in Chandler, Arizona; no later confirmation was found.

Applies to: All nine models.

What this means, and how to check it →res.cloudinary.com ↗americanwhirlpool.com ↗

What American Whirlpool says about itEach claim, what the documents show, and any catch

What American Whirlpool leads with, where it covers the MB4, and what the documents show.

CommonMAAX Force anti-turbulence currentSalespeople lead with MAAX Force: two or three swim jets fed through a manifold with 'Anti-Turbulence' technology, which the maker…Four of the nine models don't get it

What they saySalespeople lead with MAAX Force: two or three swim jets fed through a manifold with 'Anti-Turbulence' technology, which the maker says gives a powerful, smooth, fully adjustable stream across a 30-inch lane and beats propellers and paddlewheels.

What the documents showThe jets, their counts and the 30-inch lane are published. The claim of beating propellers comes with no flow figure or test, the pumps also feed the seats through a diverter valve, and air can be let into the stream (the manual says to close it for swimming).

Who else does itMulti-jet swim currents with a brand name are the norm: Master Spas sells six airless AquaSpeed VSP jets on its Challenger, Endless Pools an airless four-jet SwimCross, Hydropool its V-Twin jets.

Applies to: DM8, MB4, ML4, MX5, MX6

The catch

Four of the nine models don't get it. The RF2, RB4 and RL4 use four 'Turbo' or 'Power' swim jets on two pumps, and the RL5 two unnamed swim jets on what its spec sheet lists as one pump. No stream width is published for any of them, and the maker publishes no flow number for any of its currents.

CommonGalvanized steel frame, lifetime frame warrantyEvery PowerPool sits on a zinc-coated steel frame and a sealed ABS bottom pan that can't rot, and the frame is warranted for as…The shell gets 5 years, not life

What they sayEvery PowerPool sits on a zinc-coated steel frame and a sealed ABS bottom pan that can't rot, and the frame is warranted for as long as you own the spa. Dealers add that it's 'appliance grade' and can be restored to factory spec in your yard.

What the documents showThe steel frame, ABS pan and lifetime frame line are all in maker documents. But the maker publishes no gauge, and the lifetime promise covers the frame, not the shell that holds the water.

Who else does itSteel frames aren't unusual among the swim spa brands we researched: Endless Pools' E-Series (14-gauge galvanized), Jacuzzi's J-16 PowerPro (galvanized), Hydropool (steel) and Wellis (stainless steel) use them, while Master Spas, Cal Spas and Artesian use wood and Bullfrog a molded composite. Vita Spa's twin models share the MAAX frame.

The catch

The shell gets 5 years, not life. The same card covers the fiberglass vessel against water loss, its surface, and the equipment, plumbing and labor for only 5 years, and the side panels for 2. All coverage ends if the spa is sold, and if MAAX replaces the spa, removing the old one and installing the new one are the owner's cost.

Few othersNorthern Exposure insulation instead of foamInstead of spray foam, the cabinet walls, floor and cover are lined with copper-backed recycled fiber and wrapped in 3M Thinsulate…Every model passes California's limit by 1 watt

What they sayInstead of spray foam, the cabinet walls, floor and cover are lined with copper-backed recycled fiber and wrapped in 3M Thinsulate to hold pump heat, which also leaves the plumbing reachable for repairs.

What the documents showThe service-access benefit is real: no foam to cut through. The efficiency claim has no R-value or test behind it, and the manual warns the heat-capturing design can push the water above its set temperature in warm weather ('thermal creep').

Who else does itThe copper, recycled-fiber and Thinsulate stack is MAAX's patented design (US 9,938,740), used by MAAX's two brands, American Whirlpool and Vita Spa. Other makers mostly fill with foam or use their own blanket systems.

The catch

Every model passes California's limit by 1 watt. Each American Whirlpool swim spa's California listing reports standby power exactly 1 watt under the most its size is allowed (RL4: 541 of 542 W; MX5: 655 of 656 W). In 2018 MAAX Spas settled with California for $152,500 over spas offered for sale there in 2015-2017 without testing before certification.

CommonBuilt-in swim trainerThe topside runs a swim trainer with preset and custom drills, warm-up and cool-down, and lights that change color with the…

What they sayThe topside runs a swim trainer with preset and custom drills, warm-up and cool-down, and lights that change color with the current's intensity; MAAX pitched programmable speed levels and a light system that signals speed changes when it launched its 16-foot model.

What the documents showThe drills, timers and light feedback are documented in the Gecko in.k1000 section of the owner's manual. The number of speed steps isn't published: the manual says it depends on the spa's configuration, and the listed pumps are two-speed except the MX5's and MX6's two single-speed 2.5 hp pumps.

Who else does itProgrammable currents are standard at this price: Endless Pools publishes 31 pace settings on its E500 and Hydropool ten speeds on its Aquatic models.

Warranty5 yr structure · 5 yr equipment · 5 yr labor

Years of cover as American Whirlpool publishes them. Who pays labor, travel and removal matters as much as the years, so read the card before you sign.

Structure: 5 years
Shell surface: 5 years
Equipment: 5 years
Plumbing: 5 years
Cabinet: 2 years
Labor: 5 years
Transferable: No

What the card saysTerms run from the original installation date or one year after manufacture, whichever comes first.

Terms run from the original installation date or one year after manufacture, whichever comes first. Excludes the insulated cover and any accessory added after manufacture. Travel and reasonable labor charges may be billed for service calls. If MAAX replaces the spa, removing the old one and delivering and installing the new one are the owner's cost, and it isn't liable for removing decks or other fixtures. Every side panel must be removable without obstruction. Void after unprotected freezing, water-chemistry damage, or repairs by anyone other than an authorized MAAX Spas servicer; damage from an uneven or insufficient foundation, or from running the water outside 32-120°F, counts as abuse that may void it, and commercial use isn't covered. Micro-crazing from sun exposure without the cover isn't covered. Void if the serial number label is missing; the card asks for registration within 30 days of purchase, and the 2026 manual (p.64) says to return the card to the dealer after installation to get prompt warranty service.

Read American Whirlpool’s warranty document ↗