ThermaSol vs Mr. Steam: Which Steam Shower Generator Fits Your Home?

Steam generator comparison

ThermaSol vs Mr. Steam is less a question of which brand is better than of which brand's rules suit your shower, your walls and your generator location. Sauna Republic is an authorized dealer of both, and this guide compares ThermaSol's PRO Series III with Mr. Steam's MS, MS Super and MAX generators using each manufacturer's own documents.

ThermaSol vs Mr. Steam at a glance

For each brand on its own, see our ThermaSol steam generator buying guide and Mr. Steam steam generator buying guide. The table sets the two lines side by side.

Note that the distance row compares a distance with a pipe length.

Sizing: same measurements, two methods

Both brands start by multiplying the shower's length, width and height in feet. What happens next is where they part.

ThermaSol: volume and ceiling height

ThermaSol's installation manual says the number in each model name is its maximum capacity in cubic feet with a ceiling of 8 feet or less, and its product page states: "Wall materials do not affect generator size." For each foot of ceiling over 8 feet, the manual says to move up one model size, to a maximum of 10 feet, and ThermaSol does not recommend higher ceilings.

Mr. Steam: an adjusted volume

Mr. Steam's 2025 manual for the MS and MS Super adjusts the volume first: ceramic or porcelain tile on cement board or a mortar bed adds nothing; natural marble, stone, shale, glass block or concrete adds 50 percent; acrylic or fiberglass subtracts 40 percent. Each foot of ceiling above 8 feet then adds 15 percent, to a 10 ft maximum. The MAX manual uses the same tile, stone and ceiling adjustments, and we check MAX sizing with you before any order.

Three showers sized both ways

Because each manufacturer rates its generators for its own method, compare the models each method names, not kW. Run your own numbers in our steam shower generator size calculator, or see both methods in full in our steam shower generator guide.

Stone, acrylic and tall ceilings

With stone walls, ThermaSol's size stays the same, though it says natural stone "must be sealed regularly"; Mr. Steam's size can move up one or more models.

For acrylic, ThermaSol says walls "must be steam rated from their manufacturer" and that it "only recommends specific generators for acrylic modules." Mr. Steam's MS and MS Super manual subtracts 40 percent but also says to "select next lower-rated MS model," without saying whether both apply, so send us the enclosure details first. On ceilings, both brands prefer 8 feet where possible.

Model ranges and electrical supply

The table groups both lines by power, with current draw and ThermaSol's connection type.

ThermaSol lists one amp figure per model for its 208 to 240 VAC single-phase supply; Mr. Steam's figures are for its 240 V single-phase versions.

The PROIII-84, PROIII-140 and PROIII-240 connect with a NEMA plug; larger PRO Series III models are hardwired, and Mr. Steam's product data lists all its generators as hardwired. ThermaSol and Mr. Steam's MS and MS Super manual each call for a separate breaker; the MAX manual asks for "suitable over-current protection (fuses or circuit breaker)." Both brands specify copper conductors rated at least 90°C and a licensed electrician, who sizes the wire to the National Electrical Code and local code. Mr. Steam offers 208 V and three-phase generators on request, and the ThermaTouch2's Power Distribution Module needs 110 VAC.

Start-up and self-cleaning

ThermaSol lists FastStart Technology among the PRO Series III features and says the generator "includes a self-cleaning PowerFlush system." Its MicroTouch control lists "Operates FastStart" and "Operates Auto PowerFlush" among its features. ThermaSol's installation manual adds that "Power Flush maintenance is recommended every 1000 minutes of use."

Mr. Steam offers both as options. Mr. Steam's MS and MS Super manual says Express Steam is "only available factory installed" and that a low-power heating element and thermostat keep the tank water warm "to bring up steam quicker." Our configurator offers it for every model at the start-up speed step. AutoFlush is a separate accessory (MS81500E for MS and MS Super, CT81500 for MAX) that drains the generator about 2 hours after each use, once the water has cooled. Both Mr. Steam manuals call for opening the manual drain valve every 2 months, or more often in hard water, and both recommend AutoFlush in hard water areas.

These are each brand's descriptions, not a measured test. ThermaSol's features come with the generator; Express Steam and AutoFlush are chosen when you order.

Controls and steam heads

On each ThermaSol and Mr. Steam product page, our configurator lets you choose the control, steam head, finish and add-ons, then sends the build to us for a quote.

ThermaSol's control pages say each control "must be installed inside the shower and mounted 60 inches from the floor to the center of the controller," as far as possible from the steam head. Mr. Steam's manuals allow the control inside or outside the steam room: inside, 4 to 5 feet above the floor near the seating area and not above or near the steam head; outside, with a remote temperature probe installed inside the steam room.

ThermaSol's product page says a SteamVection kit is included with the PRO Series III, and its installation manual lists a "Steamhead Housing and Cable Kit" among the parts enclosed with the generator. The SteamVection comes round or square with an aroma well; the No-Touch is a retractable steam head in polished chrome. Each Mr. Steam control comes with a steam head in the same finish: the Aroma, the Designer (round or square) or the 16 in Linear, each with an aroma oil reservoir. ThermaSol's 15 finishes and Mr. Steam's 13 share eight names, such as polished chrome and matte black; the antique and copper finishes are ThermaSol only, and brushed nickel and brushed bronze are Mr. Steam only.

On Mr. Steam pages, the configurator also asks for start-up speed, face color, shape and add-ons such as a light, speaker, aroma pump or SteamLinx. Add-ons that wire back to the generator mean opening the wall if you add them later. Our steam shower control guide compares both lineups.

Installation differences

Both brands call for a licensed electrician and plumber and rule out installing the generator inside the steam room, outdoors or in an unheated attic. The table shows where their rules part, with Mr. Steam's two manuals in separate columns.

Both want a cold water line with a 3/8 inch connection and a shut-off valve, no valve in the steam line and a pitch that keeps condensate from pooling; Mr. Steam also recommends 15 to 20 psi feed pressure to reduce noise. Our steam shower installation requirements guide has the full checklist.

Warranty side by side

Both generator warranties start with a 2-year in-home period and cover parts for life after it, but the labor terms differ in both periods.

ThermaSol adds that units "may require factory service" and requires proof of purchase from an authorized reseller; Sauna Republic is an authorized ThermaSol and Mr. Steam dealer. Mr. Steam's controls and accessories, including AutoFlush, carry a limited 2-year warranty.

Which one fits your project

Each answer follows the manufacturers' own rules, not a ranking.

Homes vs commercial projects

Every generator here is a residential model. ThermaSol gives no warranty of any kind for its residential generators in non-residential settings such as hotels, spas, gyms or short-term rentals, and Mr. Steam's manuals say commercial or other nonresidential applications void the warranty. For those projects, see commercial steam generators compared and our commercial steam generator buying guide.

Frequently asked questions

Browse all steam shower generators, or go straight to the ThermaSol and Mr. Steam collections.

ThermaSol, Mr. Steam and the product and feature names in this guide are trademarks of their respective owners.