Residential Single-Wall Indirect Water Heaters


  • Residential Single-WallHeat Exchanger-Single-Wall 1½” O.D. glass coated (Ultonium®) carbon steel coil. The coil has a heat transfer area of 14.2 sq. ft. and a stored water volume of 2.7 Gal. Maximum supply temperature from the boiler must not exceed 250°F.
  • Factory Installed Sparge Tube System-Cold water inlet sediment reducing device helps prevent sediment build up in tank. Increases first hour delivery of hot water while minimizing temperature build up in tank.
  • Ultonium® Lining-Niles Steel Tank water heater tanks are protected from the corrosive effects of hot water by an exclusive ceramic porcelain-like coating. The Niles Steel Tank high silica Ultonium® lining provides a tough interior surface for our hot water tanks.
  • Immersed Adjustable Honeywell Aquastat-Fast acting immersion aquastat for automatic temperature control (adjustable from 80°F to 160°F)
  • Supply and Return Connections-1″ NPT female connections are located on the front for both the boiler collector supply and return.
  • 2″ Non-CFC Foam Insulation-Covers the side and top of tank, reducing the amount of heat loss. This results in less energy consumption, improved operation efficiencies and jacket rigidity.
  • Potable Water Connections-3/4″ NPT factory installed true dielectric fittings extend water heater life and eases installation.
  • Three Protective Aluminum Anode Rods-Provide added protection against corrosion for long trouble-free service.
  • Steel Tank-Heavy gauge steel automatically formed, rolled and welded to assure a continuous seam for glass lining.
  • T&P Relief Valve-Included.
  • Brass Drain Valve.
  • Limited Lifetime Warranty on tank and heat exchanger.
  • I=B=R Certified-These water heaters are rated by the Institute of Boiler and Radiation Manufacturers (I=B=R) to provide accurate performance data within the standards of the certification. The I=B=R rating is issued by the Hydronics Institute Division of GAMA and provide a recognized standard for proper comparison of hydronic appliances.

Water Heater Dimensions (Inches)
Model A B C D E F
NSW-2-30-L 22 3358 2814 3438 538 2712
NSW-2-40-RL 22 4118 3438 4178 538 2712
NSW-2-50-RL 22 4614 4018 47 538 2712
NSW-2-65-L 22 5914 5318 60 538 2712
NSW-65C-5 22 5914 5318 60 538 2712
NSW-2-80-L 24 59 5278 5934 538 2712
NSW-80C-5 24 59 5278 5934 538 2712
NSW-2-120-L 2814 6212 5534 6314 638 2812
NSW-120C-5 2814 6212 5534 6314 638 2812

Notes: All Ratings based on 200 F boiler water temperature and 50 F potable water inlet temperature.

Water Heater Performance
Model Maximum First Hour Rating (Gal/Hr) @ Continous Draw Rating (Gal/ Min) @ Approximate Boiler Output Needed for Ratings (BTU/Hr)
140°F 115°F 140°F 115°F
NSW-2-30-L 279 429 4.2 6.7 220,000
NSW-2-40-RL 288 438 4.2 6.7 220,000
NSW-2-50-RL 297 447 4.2 6.7 220,000
NSW-2-65-L 306 456 4.2 6.7 220,000
NSW-65C-5 534 820 8 12.8 420,000
NSW-2-80-L 321 470 4.2 6.7 220,000
NSW-80C-5 546 834 8 12.8 420,000
NSW-2-120-L 357 507 4.2 6.7 220,000
NSW-120C-5 583 871 8 12.8 420,000
Water Heater Performance
Model Hot Water Availability (minutes) Coil Heat Transfer Area (Sq. Ft.) Pressure Drop at 12 GPM (Feet of Head)
NSW-2-30-L 5.5 14.4 1.3
NSW-2-40-RL 7.5 14.2 1.3
NSW-2-50-RL 9.0 14.2 1.3
NSW-2-65-L 11.0 14.2 1.3
NSW-65C-5 10.5 27.2 2.6
NSW-2-80-L 13.5 14.2 1.3
NSW-80C-5 13.2 27.2 2.6
NSW-2-120-L 20.8 14.2 1.3
NSW-120C-5 20.6 27.2 2.6
Water Heater Capacities
Model Tank Capacity (Gal) Coil Volume (Gal) Dry Weight (Lbs) Wet Weight (Lbs)
NSW-2-30-L 30 2.6 140 404
NSW-2-40-RL 40 2.6 168 514
NSW-2-50-RL 50 2.6 196 623
NSW-2-65-L 60 2.6 196 704
NSW-65C-5 58 5.0 265 768
NSW-2-80-L 75 2.6 224 861
NSW-80C-5 73 5.0 293 920
NSW-2-120-L 116 2.6 355 1324
NSW-120C-5 114 5.0 415 1370






Model_Number Capacity A.
Height
Floor to Heater Top
B.Jacket Diameter C.
Height Floor to T&P Conn.
D.
Height Floor to Water Conn.
E.
Height Floor to Exchanger Outlet
F.
Height Floor to Exchanger Inlet
G.
Height Floor to Aquastat
Approx. Shipping Weight
U.S.Gal. in. in. in. in. in. in. in. lbs.
NSW-2-30-L 30 33 5/8 22 28 3/4 34 3/8 53/8 27 1/2 11 1/2 140
NSW-2-40-L 40 36 24 29 3/4 36 3/4 5 3/8 27 1/2 11 1/2 168
NSW-2-50-L 50 36 26 29 3/4 36 3/4 5 3/8 27 1/2 11 1/2 196
NSW-2-65-L 60 59 1/4 22 53 1/8 60 5 3/8 27 1/2 11 1/2 196
NSW-2-80-L 75 59 24 52 7/8 59 3/4 5 3/8 27 1/2 11 1/2 224
NSW-2-120-L 116 62 1/2 28 1/4 55 3/4 63 1/4 6 3/8 28 1/4 11 1/2 355