Steam Generator Size Calculator

Calculate Your Generator Size

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Shower Enclosure Dimensions

Width

Depth

Height

Ceiling Height

Primary Wall Material

Your Generator
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Recommended Generator Size

Recommended Generators For Your Shower

Questions about your shower, or a result near a model's limit? Call us at (888) 833-2305 before you order.

How Each Brand Sizes a Steam Generator

ThermaSol and Mr. Steam start from the same measurement, the shower's length, width and height in feet, but they adjust it differently. Each brand rates its generators for its own method, so compare the model each brand recommends for your shower rather than comparing cubic-foot ratings across brands.

Factor	ThermaSol PRO Series III	Mr. Steam MS and MS Super
Ceramic or porcelain tile	No adjustment	No adjustment
Natural stone, marble, shale, glass block or concrete	No adjustment	Add 50%
Acrylic or fiberglass	No adjustment	Subtract 40%
9 ft ceiling	Size up one generator	Add 15%
10 ft ceiling	Size up two, or confirm with ThermaSol	Add 30% (15% per foot above 8 ft)
Over 10 ft	Confirm before ordering	Outside the published rules (10 ft maximum)

ThermaSol's PRO Series III page states that wall materials do not affect generator size. Mr. Steam's rules come from its installation manual for the MS and MS Super series; the calculator applies the same rules to the MAX series, and we confirm MAX sizing with you before you order. The calculator counts a partial foot of ceiling height as a full foot, so an 8.5 ft ceiling is sized as 9 ft; if your ceiling falls between whole feet, call us to confirm.

How to Measure Your Steam Shower

1. Measure the inside of the enclosure: width, depth and ceiling height, in feet or inches. The calculator multiplies them to get the volume in cubic feet. If you already know the volume, enter it directly and set the ceiling height.

2. Set the ceiling height: ThermaSol sizes up for 9 and 10 ft ceilings, and Mr. Steam adds 15% per foot above 8 ft. If you enter a height in the dimensions, the calculator sets this for you.

3. Choose the main wall material: it changes the Mr. Steam result only.

4. Calculate: you will see one ThermaSol model and one Mr. Steam model, or a single brand if you selected one. Each recommendation links to the product page, where you can choose the control, steam head and finish.

Electrical Requirements

ThermaSol: PRO Series generators require a 208 to 240 V single-phase power supply with a dedicated breaker.

Mr. Steam: current draw at 240 V, single phase, by model. Mr. Steam bases wire sizes on copper conductors rated for at least 90°C, its MS and MS Super manual calls for a separate circuit breaker, and 208 V and three-phase generators are available on request.

Mr. Steam model	Power	Current draw
MS90R	5 kW	21 A
MS150R	6 kW	25 A
MS225R	7.5 kW	32 A
MS400R	9 kW	38 A
MSSUPER1R	10 kW	42 A
MSSUPER2R	12 kW	50 A
MSSUPER3R	15 kW	63 A
MX4R	20 kW	84 A
MX5R	24 kW	100 A
MX6R	30 kW	125 A

Have a licensed electrician confirm your panel capacity and size the circuit before you order.

Where the Generator Goes

ThermaSol: the generator can be installed up to 50 feet away from the shower.

Mr. Steam (MS and MS Super): install the generator as near as practical to the steam room, typically in a closet, vanity cabinet, heated attic or basement, with at least 12 inches clear at both ends and on top. Never install it inside the steam room or in an unheated attic. Mr. Steam's sizing allows up to 60 feet of insulated steam piping between the generator and the steam room.

Steam Generator Brands We Carry

ThermaSol PRO Series III

Seven generators from 6 to 24 kW, rated for showers up to 84, 140, 240, 395, 575, 750 and 1,200 cubic feet. ThermaSol lists FastStart, which it describes as steam in seconds, not minutes, a self-cleaning PowerFlush system and patented Smart Steam, which it says delivers precise temperature control and steady steam, as PRO Series III features. It also lists a SteamVection kit and a stainless steel drain pan as included.

ThermaSol gives PRO Series generators a two-year limited in-home warranty, followed by a factory limited warranty that replaces defective parts for the life of the product for the original purchaser.

Mr. Steam MS, MS Super and MAX

Ten generators from 5 to 30 kW: the MS series (5 to 9 kW), MS Super (10 to 15 kW) and MAX (20 to 30 kW). Each comes in a standard version or an Express Steam version, which starts producing steam sooner. AutoFlush, which flushes sediment from the generator two hours after each session, and the SteamLinx Wi-Fi module for smartphone control are add-ons.

Mr. Steam lists the United States as the generators' country of origin and gives them a limited lifetime warranty in the US and Canada: in-home service, parts and labor for two years, then parts for the life of the generator.

FAQ

ThermaSol and Mr. Steam publish different sizing rules and rate their generators for those rules. For a 3 x 4 x 8 ft tiled shower (96 cubic feet), ThermaSol's rules call for the PROIII-140 (8 kW) and Mr. Steam's for the MS150R (6 kW). Compare the model each brand recommends, not cubic-foot ratings across brands.

For ThermaSol, no: its PRO Series III page states that wall materials do not affect generator size. For Mr. Steam, yes: its MS and MS Super manual adds 50% for natural stone, marble, shale, glass block or concrete, subtracts 40% for acrylic or fiberglass, and makes no adjustment for ceramic or porcelain tile.

ThermaSol says to size up one generator for a 9 ft ceiling, and two for a 10 ft ceiling or to confirm with its team. Mr. Steam's MS and MS Super manual adds 15% for each foot above 8 ft, up to a 10 ft maximum. The calculator counts a partial foot as a full foot. For a ceiling above 10 ft, call us before you order.

ThermaSol allows up to 50 feet between the generator and the shower. For MS and MS Super generators, Mr. Steam recommends a closet, vanity cabinet, heated attic or basement as near as practical to the steam room, never inside the steam room or in an unheated attic, with up to 60 feet of insulated steam piping.

A dedicated circuit. ThermaSol PRO Series generators require a 208 to 240 V single-phase supply with a dedicated breaker. Mr. Steam generators draw from 21 A (MS90R) to 125 A (MX6R) at 240 V. Have a licensed electrician size the circuit.

Not the control. ThermaSol lists a SteamVection kit and a stainless steel drain pan as included with the PRO Series III, and each Mr. Steam control comes with a steam head. On each generator's product page, our configurator lets you choose the control, steam head and finish and sends the build to us for a quote.

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How To Use Our Steam Generator Size Calculator

Step 1: Choose Your Brand

ThermaSol and Mr. Steam use different sizing rules, so the calculator recommends one model for each brand. Leave it on All Brands to see both, or pick one brand. You can switch brands after calculating.

Step 2: Enter Your Shower Dimensions

Measure the interior width, depth and ceiling height of the enclosure, in feet or inches. Already know the volume? Enter the total cubic feet instead.

Step 3: Set the Ceiling Height

ThermaSol sizes up for 9 and 10 ft ceilings, and Mr. Steam adds 15% per foot above 8 ft. A partial foot counts as a full foot. If you entered a height, this is set for you; if you entered total cubic feet, choose it here.

Step 4: Select Your Wall Material

ThermaSol does not adjust for wall material. Mr. Steam adds 50% for natural stone, marble, shale, glass block or concrete and subtracts 40% for acrylic or fiberglass.

Step 5: View Your Results

Click Calculate Generator Size to see the recommended model for each brand, with a link to its product page. If your result is near a model's limit, or you have questions about your shower, call us before you order.

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