Mr. Steam MS vs Super vs Max Steam Generators: Which Series Fits?

Mr. Steam sells its residential steam generators in three size tiers, MS, Super and Max, and the right one depends on your steam room's adjusted cubic feet. This guide compares them using the specs on our product pages. Browse the full Mr. Steam collection or all steam shower generators to see everything in stock.

Short answer

Choose the MS Series (5 to 9 kW, up to 257 cu ft) for most tiled home steam showers, the Super Series (10 to 15 kW, up to 482 cu ft) for larger or stone-walled rooms, and the Max Series (20 to 30 kW, up to 964 cu ft) only for very large steam rooms. Size by Mr. Steam adjusted volume, then pick the next model up if you are close.

The three series side by side

Specifications are from Mr. Steam as listed on our product pages. Prices are the lowest listed for the series and can change.

Every model in each series

How to size it

Mr. Steam sizes by cubic feet, adjusted for the walls and ceiling. Measure length by width by height, then apply these rules from the product pages: add 50% for natural stone, marble, glass block or concrete; add 0% for ceramic or porcelain tile on cement board; subtract 40% for acrylic or fiberglass; and add 15% for each foot of ceiling above 8 feet, up to 10 feet.

Two worked examples, using that rule. A tiled 6 by 4 foot steam room with an 8 foot ceiling is 192 cubic feet, which fits the 9 kW MS (257 cu ft). The same room in natural stone adjusts to 288 cubic feet, which moves you to the 10 kW Super (339 cu ft). Our steam generator size calculator runs the numbers for your room.

Power and wiring

All three are hardwired on a dedicated circuit with its own breaker and a disconnect within sight, installed by a licensed electrician. The jump between tiers is big: the product pages list 25A for the MS 6 kW, 42A for the Super 10 kW at 240V and 97A for the Max 20 kW at 208V. Check your panel capacity before you pick a tier, and read steam shower generator electrical requirements for how to plan the circuit.

Express Steam, controls and extras

Each model is also offered with Express Steam. On a model like the MS 9 kW with Express Steam, Mr. Steam factory-installs a low-power heating element and thermostat that keep the tank water warm, so steam comes up quicker. On our site it adds $350 to the matching standard generator.

You also need a control and a steamhead, sold separately. The simplest choice is the iTempo, and the iSteamX adds a touchscreen with Wi-Fi and Bluetooth. Our guide to Mr. Steam controls compared walks through iTempo, TempoTouch, TempoFlex and iSteamX.

If you are weighing brands

ThermaSol makes comparable generators, and we cover them in ThermaSol PRO Series I vs II vs III. For a refresher on the basics, see the different types of steam generators, and if you are converting an existing shower, what it costs to make your shower a steam shower.

Which one should you buy?

Work through three questions. What is your adjusted room volume? Which generator rating covers it, with a little headroom? And can your electrical panel support that tier? If you land between two sizes, the larger model is the safer choice, because a generator rated close to the limit has less room for stone, glass or a taller ceiling. Choose Express Steam if quick start-up matters to you, add a control that suits how you want to use the shower, and plan the plumbing and electrical with licensed trades. The Super and Max tiers are not upgrades for their own sake, so buy the smallest tier that covers your room.

The same limited lifetime warranty on the generator, with 2 years in-home, is listed on the MS, Super and Max pages, so warranty does not change by tier. For a small shower, the Steam@Home 3kW package is the compact alternative at a lower price. If you want help, call us at (945) 280-3243 with your dimensions and wall material.

Frequently asked questions

What is the difference between Mr. Steam MS, Super and Max?

They are size tiers. The MS Series runs 5 to 9 kW for rooms up to 257 cubic feet, the Super Series runs 10 to 15 kW for up to 482 cubic feet, and the Max Series runs 20 to 30 kW for up to 964 cubic feet, all by Mr. Steam adjusted room volume.

Which series do most homes need?

A typical home steam shower with tile walls fits the MS Series. Stone, a tall ceiling or a larger room can push you into the Super Series. The Max Series is for very large rooms.

Do all three series use the same controls?

The MS and Super generators work with Mr. Steam controls including iSteamX, iTempo, TempoFlex and TempoTouch. The Max Series lists the same control families, but control packages are sold separately for MS and Super versus Max, so check the package listing.

What does Express Steam do?

On the Express Steam models, Mr. Steam factory-installs a low-power heating element and thermostat that keep the water in the tank warm so steam comes up quicker. It adds $350 to the generator price on our site.

Are Mr. Steam generators 240V or 208V?

Both are offered. The listings are available as 240V and 208V single-phase models, so match the version to the power at your home and have a licensed electrician confirm the circuit.

How does ceiling height change the size I need?

Per Mr. Steam, add 15% to the room volume for each foot of ceiling above 8 feet, up to 10 feet.

What warranty applies?

The MS, Super and Max pages list a limited lifetime warranty on the generator, including 2 years in-home, for residential use. Read the full manufacturer terms.

Is there a smaller option than the MS Series?

Yes. The Steam@Home 3kW package is for small steam rooms of 60 to 75 cubic feet, about a 3 by 3 foot shower, and lists a 1-year limited warranty.