Print Back
Master-Fit® Standard Draft Commercial Gas Water Heaters
Unit of Measure
Items Master-Fit® Standard Draft Commercial Gas Water Heaters
BTR-251 (A)
Master-Fit® Standard Draft Commercial Gas Water Heaters
Master-Fit® Standard Draft Commercial Gas Water Heaters
BTR-305 (A)
Master-Fit® Standard Draft Commercial Gas Water Heaters
Master-Fit® Standard Draft Commercial Gas Water Heaters
BTR-120
Master-Fit® Standard Draft Commercial Gas Water Heaters
Master-Fit® Standard Draft Commercial Gas Water Heaters
BTR-154
Master-Fit® Standard Draft Commercial Gas Water Heaters
Master-Fit® Standard Draft Commercial Gas Water Heaters
BTR-180
Master-Fit® Standard Draft Commercial Gas Water Heaters
Manufacturer N/A A. O. Smith®
Input Power N/A 251000 BTU/hr N/A 305000 BTU/hr N/A 120000 BTU/hr N/A 154000 BTU/hr N/A 180000 BTU/hr
Tank Capacity N/A 65 U.S. gal246 L N/A 65 U.S. gal246 L N/A 71 U.S. gal268 L N/A 81 U.S. gal307 L N/A 81 U.S. gal307 L
Recovery at 40 ºF Temperature Rise N/A 608 gal/h N/A 739 gal/h N/A 291 gal/h N/A 373 gal/h N/A 434 gal/h
Recovery at 22 ºC Temperature Rise N/A 2303 L/h N/A 2799 L/h N/A 1102 L/h N/A 1412 L/h N/A 1643 L/h
Recovery at 100 ºF Temperature Rise N/A 243 gal/h N/A 296 gal/h N/A 116 gal/h N/A 149 gal/h N/A 175 gal/h
Recovery at 56 ºC Temperature Rise N/A 921 L/h N/A 1120 L/h N/A 439 L/h N/A 564 L/h N/A 659 L/h
Recovery at 140 ºF Temperature Rise N/A 174 gal/h N/A 211 gal/h N/A 83 gal/h N/A 107 gal/h N/A 124 gal/h
Recovery at 78 ºC Temperature Rise N/A 658 L/h N/A 800 L/h N/A 314 L/h N/A 405 L/h N/A 469 L/h
Schematic N/A
Schematic Drawing for Master-Fit® Standard Draft Commercial Gas Water Heaters (BTR-120 to BTR-400 (A))
Dimension A N/A 75 in191 cm N/A 75 in191 cm N/A 69-3/4 in177 cm N/A 73 in185 cm N/A 67-1/2 in171 cm
Dimension B N/A 4-1/2 in12 cm N/A 4-1/2 in12 cm N/A 4-1/4 in11 cm N/A 4-1/4 in11 cm N/A 4-1/2 in12 cm
Dimension C N/A 65-3/4 in167 cm N/A 65-3/4 in167 cm N/A 59-1/2 in151 cm N/A 66-1/2 in169 cm N/A 62 in157 cm
Dimension D N/A 57-1/4 in145 cm N/A 57-1/4 in145 cm N/A 50-7/8 in129 cm N/A 57-7/8 in147 cm N/A 53-5/8 in136 cm
Dimension E N/A 20 in51 cm N/A 20 in51 cm N/A 19-11/16 in50 cm N/A 19-11/16 in50 cm N/A 20-1/2 in52 cm
Dimension F N/A N/A N/A 19 in48 cm N/A 19 in48 cm N/A 21 in53 cm
Dimension G N/A 1/2 in
Dimension H N/A 58-3/4 in149 cm N/A 58-3/4 in149 cm N/A 51-7/8 in132 cm N/A 59 in150 cm N/A 54-5/8 in139 cm
Dimension I N/A 8 in20 cm N/A 8 in20 cm N/A 6 in13 cm N/A 6 in15 cm N/A 6 in15 cm
Dimension J N/A 27-3/4 in71 cm
Standard Shipping Weight N/A 750 lb341 kg N/A 750 lb341 kg N/A 400 lb182 kg N/A 470 lb213 kg N/A 470 lb213 kg
ASME Shipping Weight N/A 862 lb391 kg N/A 862 lb391 kg N/A N/A N/A
Type N/A Liquid Propane Gas Natural Gas
Maximum Hydrostatic Working Pressure N/A 160 psi
Thermal Efficiency N/A 80 %
Maximum Gas Supply Pressure N/A 14 inWc
Minimum Gas Supply Pressure N/A For Liquid Propane Gas: 11 inWcFor Natural Gas: 4.5 inWc
Manifold Pressure N/A For Liquid Propane Gas: 10 inWcFor Natural Gas: 3.5 inWc
Industry Standards N/A ANSI Z-21.10.3 - CSA 4.3 ASHRAE/IESNA 90.1 ASME Certified CSA® Certified NSF UL® Listed
Features N/A The Master-Fit® BTR series provides outstanding performance and maximum installation flexibility for both new construction and replacement applications. Multiple options for placement of water connections and low installation clearances are additional installer-friendly features.

The Eliminator™ Self-Cleaning System
  • Designed to significantly reduce or eliminate sediment build-up inside the tank.
  • Reduced sediment build-up maintains rated thermal efficiency and reduces water heating costs.
  • Self-cleaning system maximizes tank life.
Factory-Installed Draft Diverter and Automatic Flue Damper (BTR-120-400 Models)
  • Low-profile draft diverter helps for installation in tight spaces.
  • Automatic motorized flue damper helps minimize standby heat loss.
  • BTR-500 Model features induced draft design and no damper.
Three Water Connection Options for Added Flexibility
  • Hot and cold water connections can be made through front, top or rear of unit.
  • Eliminator™ system operates when cold water is connected through front.
Permaglas® Ultra Coat™ Glass Lining
  • Exclusive process provides superior protection against corrosion.
  • CoreGard™ anode rods with stainless steel core provide additional corrosion protection.
Intermittent Electronic Ignition
  • Eliminates standing pilot, saves energy.
  • Includes power ON/OFF switch.
  • Provides flame failure response in less than one second.
Testing and Certifications N/A Factory-Installed, CSA® Certified and ASME Rated T&P Relief Value
  • Design-certified by UL (Underwriters Laboratories), according to ANSI Z.21.10.3 - CSA® 4.3 standards governing storage-type water heaters
  • Meets the thermal efficiency and standby loss requirements of the U.S. Department of Energy and current edition of ASHRAE/IESNA 90.1
  • Design-certified by Underwriters Laboratories Sanitation to NSF Standard 5 for 180 ºF (82 ºC) water
  • Optional ASME tank construction available
Other Master-Fit® Features N/A Fully Automatic Control System
  • Manual-reset gas shut-off device prevents excessive water temperature
  • Adjustable thermostat with 120 to 180 ºF range
  • Gas pressure regulator and pilot filter
Handhole Cleanout
  • Allows easy access to tank interior for cleaning
Plug Kits
  • Pipe nipples and caps included to plug unused water connections MASTER-FIT® OPTIONS:
Manifold Kits for Multiple Heater Installations
  • 2-unit kit, Part Number 9003426205
  • 3-unit kit, Part Number 9003427205
  • 4-unit kit, Part Number 9003428205
Optional Leg Kit to Meet NSF Standard 5
  • For all BTR models, Part Number 9003425205
Mechanical Venting Kits
  • For BTR-120 through BTR-200, Part Number 9006015005
  • For BTR-250 through BTR-400, Part Number 9006016005
  • For installation of approved power venter to operate in conjunction with water heater thermostat
  • Field wiring should conform to latest version of the National Electric Code ANSI/NFPA No.70
Warranty N/A
  • 3-Year Limited Tank Warranty.
Note N/A Electrical requirements: 120 VAC, 0.7 Amp, Electrical requirements with Power Venter: 120 VAC,3.0 FLAAmps.

Model Shipped with 8" to 6" vent reducer. Certified for both 6" to 8" vent.
N/A Electrical requirements: 120 VAC, 0.7 Amp, Electrical requirements with Power Venter: 120 VAC,3.0 FLAAmps. N/A Electrical requirements: 120 VAC, 0.7 Amp, Electrical requirements with Power Venter: 120 VAC,3.0 FLAAmps.

Approved for 5" venting using field supplied 6" to 5" reducer.
N/A Electrical requirements: 120 VAC, 0.7 Amp, Electrical requirements with Power Venter: 120 VAC,3.0 FLAAmps. N/A Electrical requirements: 120 VAC, 0.7 Amp, Electrical requirements with Power Venter: 120 VAC,3.0 FLAAmps.