See it at Amerec: AK9
Amerec's own page for the AK9. Not a paid link.
AK9 vs MS400R
Amerec AK9 and Mr. Steam MS400R, compared on the figures their makers publish. Both are steam generators whose stated room-size ratings overlap, read before each maker's own sizing rule.
The makers' figures side by side
| Specification | Amerec AK9 | Mr. Steam MS400R |
|---|---|---|
| Heater output | Watts: 9000 (240 V); 9000 (208 V) | kW: 9 |
| Room size the maker rates it for | Steam Room Cu Ft: Min 150, Max 300 | Room Volume (cu. ft.): 162-257 |
| Voltage | 240 and 208 volt models can be wired in the field for 1 or 3 phase power. | 2401 after model number denotes a 240V/1PH generator; B1 after model number denotes a 208V/1PH generator; Other voltage and phase combinations available upon request |
| Breaker / current | 240 V: 1 Phase Amps 38, Breaker 50; 3 Phase Amps 22, Breaker 30. 208 V: 1 Phase Amps 43, Breaker 60; 3 Phase Amps 25, Breaker 40 | Amps 240/1PH: 38; Wire Size AWG: 8 |
| Dimensions | 16-1/2" x 6-1/4" x 15" | 14.5" x 14.75" x 6.75" |
| Weight | — | Shipping Weight: 27 lbs. |
| Water and drain connections | Water Inlet – 3/8” NPT; Pressure Relief Valve – 3/4” NPT; Steam Outlet – 1/2” NPT; Drain Outlet – 3/4” NPT | Steam Outlet (3/4" NPT) Water Supply (3/8" NPT) Safety Valve (3/4" NPT) Steam Head (3/4" NPT) Drain (1/2" NPT) |
| Control included | 1 Control Required, additional may be connected. Compatible with the K2, K3, KT3, K4 controls. | Required Equipment: SteamX, iTempoTouch, TempoFlex, iTempo, Controls |
| Drain and flush | Amerec’s ADK auto drain option is highly recommended to automatically drain and flush the generator after every steam bath; If you do not buy the auto drain, your tank will need to be flushed monthly, or more often, depending on local water conditions | Optional Equipment: ChromaX, AudioX, Recessed Light, MS Wallseat, AutoFlush, Drip Pan |
| Safety listing | ETL Listed for USA and Canada | US and Canadian UL listed, and CE and NOM certified |
| Warranty | Limited Lifetime Warranty; all component parts for five years from the date of installation | Limited lifetime generator parts warranty |
| Price on the maker's site | $3,620 (steam builder on amerec.com, 29 Sep 2026) | $4,300 (List Price, Mr. Steam 2025 price book on docs.mrsteam.com, read 29 Sep 2026) |
Each figure is the maker's own, as cited row by row on the AK9 and MS400R pages and listed in the sources below. A dash means the figure is not on the maker pages we cite. Each maker states its own sizing rule, if any; read it on the product page.
Where to buy
See it at Mr. Steam: MS400R
Mr. Steam's own page for the MS400R. Not a paid link.
Where the published figures differ
- Heater output: AK9: Watts: 9000 (240 V); 9000 (208 V). MS400R: kW: 9.
- Room size the maker rates it for: AK9: Steam Room Cu Ft: Min 150, Max 300. MS400R: Room Volume (cu. ft.): 162-257.
- Voltage: AK9: 240 and 208 volt models can be wired in the field for 1 or 3 phase power. MS400R: 2401 after model number denotes a 240V/1PH generator; B1 after model number denotes a 208V/1PH generator; Other voltage and phase combinations available upon request.
- Breaker / current: AK9: 240 V: 1 Phase Amps 38, Breaker 50; 3 Phase Amps 22, Breaker 30. 208 V: 1 Phase Amps 43, Breaker 60; 3 Phase Amps 25, Breaker 40. MS400R: Amps 240/1PH: 38; Wire Size AWG: 8.
- Dimensions: AK9: 16-1/2" x 6-1/4" x 15". MS400R: 14.5" x 14.75" x 6.75".
- Water and drain connections: AK9: Water Inlet – 3/8” NPT; Pressure Relief Valve – 3/4” NPT; Steam Outlet – 1/2” NPT; Drain Outlet – 3/4” NPT. MS400R: Steam Outlet (3/4" NPT) Water Supply (3/8" NPT) Safety Valve (3/4" NPT) Steam Head (3/4" NPT) Drain (1/2" NPT).
- Control included: AK9: 1 Control Required, additional may be connected. Compatible with the K2, K3, KT3, K4 controls. MS400R: Required Equipment: SteamX, iTempoTouch, TempoFlex, iTempo, Controls.
- Drain and flush: AK9: Amerec’s ADK auto drain option is highly recommended to automatically drain and flush the generator after every steam bath; If you do not buy the auto drain, your tank will need to be flushed monthly, or more often, depending on local water conditions. MS400R: Optional Equipment: ChromaX, AudioX, Recessed Light, MS Wallseat, AutoFlush, Drip Pan.
- Safety listing: AK9: ETL Listed for USA and Canada. MS400R: US and Canadian UL listed, and CE and NOM certified.
- Warranty: AK9: Limited Lifetime Warranty; all component parts for five years from the date of installation. MS400R: Limited lifetime generator parts warranty.
- Price on the maker's site: AK9: $3,620 (steam builder on amerec.com, 29 Sep 2026). MS400R: $4,300 (List Price, Mr. Steam 2025 price book on docs.mrsteam.com, read 29 Sep 2026).
Figures we cite for only one of the two: weight (only Mr. Steam's cited pages give it). Ask the other maker before treating the two as equal on those points.
Read each one in full
Amerec AK9
Amerec · steam generator · 9 kW · rated by the maker for 150–300 cu ft
Mr. Steam MS400R
Mr. Steam · steam generator · 9 kW · rated by the maker for 162–257 cu ft
Sources
- Amerec: steam builder — Amerec
- Amerec: warranty — Amerec
- Amerec: Amerec AK Steam Generator with K2 and K3 (PDF) — Amerec
- Amerec: residential steam bath generator 100 — Amerec
- Amerec: faq — Amerec
- Mr. Steam: TS0041 90R 400R (PDF) — Mr. Steam
- Mr. Steam: PRICEBOOK (PDF) — Mr. Steam
- Mr. Steam: generators — Mr. Steam