Electric Low Capacity

Model E

Electric cement lined water heater Model E
  • Light Duty
  • 6 - 120 Gallon Capacity
  • Up to 12KW - 1 Phase or 3 Phase

Model HE / HSE

Electric horizontal ceiling hung water heater Model HE/HSE
  • Horizontal, Ceiling Hung
  • 20 or 30 Gallon Capacity
  • Up to 20 KW - 1 or 3 Phase

Model PBX

Hybrid electric heat pump water heater Model PBX
  • Heat Pump Water Heater
  • 40 - 120 Gallon Capacity
  • 1 or 3 Phase

Model CE 110

Point-of-use electric water heater Model CE110
  • Point-of-Use
  • 1 Gallon Capacity
  • 1000 or 450 Watts - 1 Phase

Model Tankless

Electric tankless point-of-use water heater Model R
  • Whole House / Point-of-Use
  • Availabe 3 thru 27 KW - 1 Phase

Model J

Electric booster water heater Model J
  • Booster Heater
  • Provides 180°F water
  • Up to 88 KW - 1 or 3 Phase

Model JTX

Electric tankless booster heater Model JTX
  • Tankless Booster Heater
  • Provides 180°F water
  • 11 to 54 KW - 1 or 3 Phase

Model SE

Commercial heavy duty electric storage water heater Model SE
  • Light Duty
  • 6-120 Gallon Capacity
  • Up to 58 KW - 3 Phase

Model HX / TX

Electric tankless water heater Model TX
  • Tankless Commercial
  • Highly efficient tankless
  • Up to 54 KW - 1 or 3 Phase

Model SH & H

Large capacity electric storage tank water heater Model SH
  • Large Capacity
  • 80-5000 Gallon Capacity
  • All KW ratings - 1 or 3 Phase
     

Model GX

Gas tankless water heater Model GX
  • Commercial Gas Tankless
  • Integrated Pump
  • 200,000 and 250,000 BTUs

Model GXT

Condensing gas storage tank water heater Model GXT
  • Integrated Tank with Tankless
  • Hydrastone Cement
  • 200,000 to 250,000 BTUs

Model DGX

DI/RO gas fired tankless water heater Model DGX
  • DI/RO Water Heater
  • Gas Tankless
  • 199,950 and 250,000 BTU

Model JBX

Condensing gas tankless booster water heater Model JBX
  • Gas Tankless Booster
  • For Commercial Kitchens
  • 150,000 / 200,000 / 250,000 BTU

Model GSE

Condensing gas storage tank water heater Model GXT
  • Gas Storage Tank
  • Hydrastone Cement
  • 200,000 to 250,000 BTUs
   

Model ST

Steam fired water heater large capacity Model ST
  • Storage Type
  • 80-5000 Gallon Capacity
  • ASME Stamped

Model STX

Semi-Instantaneous Steam Fired Water Heater Model STX
  • Semi-Instantaneous
  • Space saving design
  • Provides 10,500 GPH

Model PS

Storage tank steam fired water heater Model PS
  • Light Duty
  • 80-120 Gallon Capacity
  • For low demand/recovery

Model F

Instantaneous steam fired water heater Model F
  • Instantaneous
  • 7 Sq. Ft. of floorspace
  • Up to 120 GPM
     

Model BWX

Indirect fired semi-instantaneous water heater Hubbell Model BWX
  • Semi-Instantaneous
  • Vertical or Horizontal
  • ASME Stamped

Model BW

Indirect fired storage tank water heater Hubbell Model BW
  • Storage Type
  • Vertical or Horizontal
  • 80-5000 Gallon Capacity

Model Transflow

Indirect fired storage tank water heater model T Transflow
  • Indirect Fired
  • 30-120 Gallon Capacity
  • Utilizes boiler water

Model SLN

Solar water heater Model SLN
  • Solar Heater
  • Vertical Storage Type
  • 30-120 Gallon Capacity
       

Model CR

Electric circulation heater Hubbell Model CR
  • Circulation (Instantaneous)
  • Heavy Duty Construction
  • 25-1600 KW - 1 or 3 Phase

Model ER

Electric hazardous location water heater Model ER
  • Hazardous Location
  • 10-120 Gallon Capacity
  • Up to 58 KW - 1 or 3 Phase

Model V

Electric process industrial water heater Model V
  • Process Systems & Industrial
  • ASME Stamped
  • Up to 88 KW - 1 or 3 Phase

Model ETX

Electric tankless safety shower water heater Model ETX
  • Tankless Emergency Tepid Water
  • NEMA 4 Standard
  • Up to 88 KW - 1 or 3 Phase

Model HD

DI/RO electric hot water heater Model HD
  • RO/DI Water Heater
  • Point-of-Use Heater
  • Up to 88 KW - 1 or 3 Phase

Model D

DI/RO electric hot water heater Model D
  • RO/DI Water Heater
  • 1-120 Gallon Capacity
  • Up to 88 KW - 1 or 3 Phase

Model EMV

Electric safety shower water heater Model EMV
  • Emergency Tepid Water
  • Fully packaged system
  • Integrated mixing valve

Packaged Skid

Model Packaged Skid
  • Customized to your specifications
  • Full featured system ready for your application

Model ME

Electric water heater for shipboard marine use single phase power Model ME
  • Light Duty
  • 6-120 Gallon Capacity
  • Up to 6 KW - 1 Phase

Model MSH

Electric water heater for shipboard marine use large capacity Model MSH
  • Large Capacity
  • 80-5000 Gallon Capacity
  • All KW ratings - 1 or 3 Phase

Model MSE

Electric water heater for shipboard marine use three phase power Model MSE
  • Vertical
  • 6-120 Gallon Capacity
  • 1 or 3 Phase - Up to 58 KW

Model MTX

Electric tankless water heater for shipboard marine use model MTX
  • Tankless Marine Heater
  • Provides 180°F water
  • 11 to 54 KW - 1 or 3 Phase

Model 177

Naval shipboard marine electric water heater Hubbell Model 177
  • MIL Spec Navy Heaters
  • Comforms to MIL-H-965
  • Shock and EMI protection

Integrated Skid

Turn-key hot water system
  • Customized to your specifications
  • Full featured system ready for your application
   

Heating Elements

Electric immersion tubular style heaters
  • Immersion Electric Heaters
  • Flanged or Screw Plugs Types
  • All KW ratings - 1 or 3 Phase

Heat Transfer Coils

Heat exchanger and heating coil water heaters
  • Immersion Heat Transfer Coils
  • U tube type
  • Range of Materials
   
       
Electric High Capacity
Gas Fired
Steam Fired
Indirect
Special Purpose
Marine
Elements & Exchangers
Resource Center
Semi-Instantaneous Steam Fired Water Heater Model STX
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Model STX

Packaged Semi-Instantaneous Steam Fired Water Heater

Shell and Tube Style Heater

The Model STX is a fully packaged semi-instantaneous steam fired water heater which utilizes steam for heating potable water. The entire package is designed to be a reliable and long lasting source for hot water. Each component is carefully selected to ensure high performance in even the most demanding application. Whether you are heating potable water in a commercial building or process water in an industrial application, you can select a Hubbell STX model to do the job. When you specify and install a Hubbell water heater, you will be provided with a quality product that is a long lasting and trouble-free source for hot water.

Learn More About Hydrastone Cement Lining

ASME
  • Reliable

    • Only high grade materials used in construction to ensure long operating life
    • Hydrastone cement lining provides superior protection and tank longevity
    • Heavy duty construction withstands demanding commercial/industrial use
  • Packaged System

    • Factory supplied with all steam controls saving time and money during installation
    • All steam operating controls are factory sized and selected to ensure reliable operation
  • Versatile

    • Full range of styles, sizes, and optional features to meet your exact heating needs

Model STX Semi Instantaneous Standard Equipment

Vessel Construction

  • Solid 90/10 vessel and built in strict accordance with the ASME Code Section VIII and stamped, certified, and registered with the National Board of Boiler and Pressure Vessel Inspectors
  • Designed for 150 psi working pressure and hydrostatically tested

Steam Water Operating Controls

  • Steam operating controls are factory selected, sized, piped and tested to ensure reliable operation
  • All steam components are factory plumbed with schedule 40 black iron pipe and ready for steam and condensate connections
  • High quality cast iron pilot operated steam control valve modulates the flow of steam through the heating coil to provide accurate water temperature control
  • Cast iron Y strainer with 20 mesh screen protects the steam controls and coil from dirt and debris in the steam supply
  • Thermostatic drip trap removes condensate from the steam supply line
  • Heavy duty cast iron float and thermostatic main condensate trap for optimum efficiency
  • All bronze integral circulating pump
  • Direct mounted steam and domestic water temperature and pressure gauges
  • High limit single solenoid safety system closes the steam supply to the heating coil should the water temperature in the tank reach the hi-limit set point. Requires 120 volt 5 amp electrical service

Heating Coil

  • Factory sized and installed copper heating coil with a gernously sized heating surface designed to ensure reliable operation
  • U-Tube heating coil constructed from single wall copper tubing designed for a maximum working pressure of 150 psi
  • Heavy duty fabvricated steel head with threaded NPT inlet and outlet connections
  • All wetted parts are non-ferrous for maximum longevity
  • Non-Ferrous tube sheet

General

  • Heavy duty 3" thick fiberglass insulation for maximum operating efficiency and minimal stand-by heat loss
  • Heavy gauge painted galvanized steel protective outer jacket
  • Heavy duty integrally welded steel supports and base for floor mounting
  • Full five (5) year Non Pro-Rated pressure vessel and a one (1) year component warranty
  • ASME rated combination T&P relief valve set at the tank working pressure and 210°F

Outline Dimensions

Model STX (Vertical)

Outline Dimensions

Model STXH (Horizontal)

Outline Dimensions

Overall Dimensions, Model STX Vertical Dimensions (Inches)

Model No. Based on 100°F Δ T Recovery Rate (40-140°F)
Base Model Recovery Rating (GPH) 40-140°F BTU/Hr Steam Supply Pressure (psi) Vertical Model STX Overall Dimensions (inches) Weight (Lbs)
Single Wall Double Wall
ABCDEABCDE
STXCN-600600500,000599463511.62517.7599.5463512.62518.75610
1587402911.62517.7599.5463512.62518.75585
2587402911.62517.7587.5402912.62518.75585
5087402911.62517.7587.5402912.62518.75585
7598.5463610.50016.7587.5402912.62518.75560
STXCN-900900750,000587.5402912.62518.7588412814.62521655
1599463511.62517.7599.5463512.62518.75610
2599463511.62517.7599.5463512.62518.75610
5087402911.62517.7587.5402912.62518.75585
7587402911.62517.7587.5402912.62518.75585
STXCN-120012001,000,000587.5402912.62518.7588412814.62521655
1575.5342312.62518.7588412814.62521615
2575.5342312.62518.7599.5463512.62518.75615
5087402911.62517.7599.5463512.62518.75585
7587402911.62517.7587.5402912.62518.75585
STXCN-150015001,250,000576352214.62521100473414.62521770
1587.5402912.62518.7588412814.62521655
2575.5342312.62518.7588412814.62521615
5099463511.62517.7599.5463512.62518.75610
7587402911.62517.7599.5463512.62518.75585
STXCN-180018001,500,000576352214.6252189412816.7523770
1576352214.6252188412814.62521770
2587.5402912.62518.7588412814.62521655
5075.5342312.62518.7588412814.62521615
7599463511.62517.7599.5463512.62518.75610
STXCN-240024002,000,000577352216.7502389412816.7523985
1576352214.62521100473414.62521770
2576352214.6252188412814.62521770
5087.5402912.62518.7588412814.62521655
7587.5402912.62518.7588412814.62521655
STXCN-300030002,500,000577352216.7502378362118.7525985
1576352214.6252189412816.7523770
2576352214.6252189412816.7523770
5076352214.6252188412814.62521770
7587.5402912.62518.7588412814.62521655
STXCN-360036003,000,000577352216.7502390422718.7525985
1577352216.7502389412816.7523985
2576352214.6252189412816.7523770
5076352214.62521100473414.62521770
7576352214.6252188412814.62521770
STXCN-420042003,500,000578362118.7502590422718.75251130
1577352216.7502378362118.7525985
2577352216.7502389412816.7523985
5076352214.6252189412816.7523770
7576352214.62521100473414.62521770
STXCN-480048004,000,000578362118.750259643332026.6251130
1577352216.7502390422718.7525985
2577352216.7502378362118.7525985
5076352214.6252189412816.7523770
7576352214.62521100473414.62521770
STXCN-600060005,000,000584372720.00026.6258737.52722311480
1578362118.7502590422718.75251130
2577352216.7502378362118.7525985
5077352216.7502389412816.7523985
7576352214.6252189412816.7523770
STXCN-750075006,250,00058737.52722.00031-----1610
1578362118.750258737.52722311130
2578362118.750258437272026.6251130
5077352216.7502390422718.7525985
7577352216.7502389412816.7523985
STXCN-900090007,500,0005-----------
1584372720.00026.6259943.53322311480
2578362118.750259943.53322311130
5078362118.7502590422718.75251130
7577352216.7502390422718.7525985
STXCN-1050010,5008,750,0005-----------
158737.52722.00031-----1610
2584372720.00026.6259943.53322311480
5078362118.750259643332026.6251130
7577352216.7502390422718.7525985
Note:
All dimensions are approximate and subject to change. Please reference the submittal drawing for actual dimensions.

Formulas

Model STX Steam Consumption Formula

Piping Layouts

Model STX Piping Layout - Single and Dual Units

Model STX Piping Layout - Single Unit with Storage Tank

Model STX Optional Equipment

Vessel

  • Alternate vessel construction:
    Stainless Steel Type 304 or 316L
  • Alternate working pressure: Specify

Heating Coil

  • Double wall tubing with a leak detection port
  • Alternate tubing material:
    Stainless Steel, 90/10 Copper-Nickel, Admiralty
  • Fabricated head constructed from:
    Stailess Steel, Copper Alloy

General

  • Type 304 stainless steel protective jacket

Operating Controls

  • A double solenoid safety system dumps over heated water in the vessel to drain in addition to closing the steam supply to the heating coil. Requires 120 volt 5 amp electrical service
  • Electric or Pneumatic operated steam control valve
  • Electric Control package for integration with Energy Management Software (EMS) and Building Automation Software (BAS). MODBUS communication to monitor the heater via RS-232 or RS-485

Model Number Designation STX and STXH



Step 1
Model:
STX = Vertical
STXH = Horizontal
Step 2
Vessel Type:
CN = 90/10 Copper-Nickel
SS = Stainless Steel
(Type 304 or 316L)

-
Step 3
Recovery Rating:
In GPH at 100°F ΔT

Step 4
Coil Type:
S = Single Wall
D = Double Wall

Example:

STXCN-3600S

A vertically installed semi-instantaneous steam fired water heater with a 90/10 Copper-Nicel pressure vessel and single wall heating coil rated to heat 3600 GPH at a 100°F temperature rise.

Model STX Specific Questions

What temperature should I set my water heater?

For typical domestic potable hot water service the temperature of your water heater at 125°F is sufficient. This prevents wasted energy (which means cost savings for you) and also decreases the possibility of scalding water burns. If you run out of hot water on this setting, increase the temperature by five degrees incrementally until your hot water needs are met. The goal is to have the temperature set just high enough to meet your needs but within safe operating parameters. Please note that a water heater in and of itself should not be relied upon as the ultimate temperature controlling source for the hot water delivered to your fixtures. Please consult local and state codes for installation of the proper and code approved (ASSE 1016, 1070, 1017) mixing devices to achieve the safe delivery of hot water to the fixtures. For a more complete information please download the whitepaper PDF titled "Understanding Potential Water Heater Scald Hazards" developed by ASSE at the following link ASSE Whitepaper

Which is better for me, a tankless or storage type water heater?

It depends. A tankless water heater is sometimes referred to as a Point-of-Use (POU) or instantaneous water heater. Due to the relative small physical size of a tankless water heater compared to a storage tank water heater, a tankless option can be advantageous from a space saving perspective and can sometimes be installed closer to where you want hot water (hence the term POU). However, tankless heaters are not suited for many applications, so it is critical that before choosing to go tankless you have carefully considered all of the factors that sometimes make the tankless option more complicated and risky compared to a storage type water heater. In particular, you should understand the operational characteristics, maintenance requirements, reparability, and sometimes significant installation requirements of a tankless water heater before making a decision. Tankless units do not store heated water like a storage type water heater; they only heat water as there is demand and therefore must be sized to meet the maximum flow for the application. In some cases a tankless water heater may improve operating efficiency, but possibly at the expense of user comfort. Hubbell tankless water heaters are available in Electric Tankless or Gas Tankless

How does my water heater ship?

All Hubbell storage type water heaters ship via common carrier and are classified by the Commodity Classification Standards Board under National Motor Freight Classification (NMFC) class 100. Each water heater is palletized and wood crated. All Hubbell tankless water heaters, when transported using common carrier, ship class 77.5. To provide the lowest transportation cost, in most cases the shipment is made on Hubbell’s account and the freight cost is added to the invoice, commonly referred to as “Pre pay and add”. For very large shipments, the most economical method (LTL or Dedicated Truck) for transporting the water heaters to the final destination will be analyzed by Hubbell's transportation department.

The heater will be installed in Canada, what is CRN?

All provinces of Canada have adopted the ASME Code and require vessels to be stamped with a provincial registration number in addition to the ASME symbol and National Board stamping. Before construction begins, one requirement has to be met in all provinces of Canada. We must submit blueprints and specification sheets in triplicate of all designs for approval and registration by the chief inspector of the province in which the vessel is to be used. After the chief inspector receives the drawings, they are checked by an engineer to determine their compliance with the Code and also with provincial regulations. A CRN number is assigned and must be stamped on the vessel in addition to the ASME symbol and National Board stamping. Once the design has been approved and registered, any number of vessels of that design can be built and used in the province where it was approved. This process is repeated for each province. The Canadian provinces also require their own manufacturer's affidavit form, with the registration number and the shop inspector's signature on the data sheets. Finally, when a vessel is delivered to a purchaser in Canada, an affidavit of manufacturer bearing registration number and the signature of the authorized shop inspector must be sent to the chief inspector of the province for which it is intended.

What hi-limit control is provided for an over-temperature condition?

Hubbell provides a solenoid safety system for over-temperature situations. An aquastat senses the over-temperature condition and trips a solenoid which shunts the steam supply to the water heater. For semi-instantaneous water heaters (STX and BWX models) Hubbell provides an additional solenoid (aptly named a double solenoid) system to shunt the steam from entering the heating coil and to dump over heated water in the vessel to drain. For storage water heaters (ST and BW models) Hubbell provides a single solenoid system to shunt the steam supply to the heating coil thus preventing further over heating. A storage tank water heater does not typically include a second soeloid to dump the over heated water to drain due to the large volume of water that would need to be drained which could potentially exceed the capacity of the local drain.

General Questions

Where can I purchase a Hubbell water heater?

There are numerous ways to purchase a Hubbell water heater depending upon the model you desire and your geographic location. The easiest way is to contact Hubbell directly at 800-647-3165 and ask for the sales department where you will be directed to either our local representative or our order entry department for quick and easy ordering.

Where can I purchase replacement parts?

Parts are available for your Hubbell water heater direct from the factory. Please call 800-647-3165 and ask for our parts department. Please have your model and serial number handy.

I don't see the size or feature I need, what do I do?

Hubbell has more than 35 product families available in over 4,000,000 configurations. There are numerous features, configurations and ratings we provide but for practical reasons are are not listed in the sales brochure. If you have a specific requirement and you do not see it in the brochure, please contact a Hubbell Sales Engineer...chances are we have what you need.

What should I know about Legionella disease?

Legionella is the bacteria responsible for Legionnaire’s Disease, an acute bacterial infection of the lower respiratory tract. This bacterium was first identified in 1977 by the Centers for Disease Control as the cause of an outbreak of pneumonia that caused 34 deaths at a 1976 American Legion Convention in Philadelphia. Pontiac Fever is a less severe, non-pneumonia, flu-like disease that is associated with and likely caused by Legionella bacteria. Legionella is a fairly common water bacterium and has been found to exist widely in many surface water sources including lakes, rivers, streams and ponds. It can also be found in ground water sources and some soils. At the levels found in these naturally occurring sources it typically does not pose a threat to public health. When the bacterium enters a domestic water system it can find an ideal host environment of warm water temperatures (105-115°F), stagnant water areas (isolated storage tanks and dead-end piping legs) and ample food sources (sediment, scale, deposits and biofilm). Under these conditions Legionella can rapidly colonize, forming higher concentrations that can pose the public health threat of Legionnaire’s Disease. There are many methods of controlling colonization of Legionella bacteria. However, a widely accepted and preferred method is to maintain the hot water system storage temperature continually at or above 140°F. Unfortunately, the elevated temperature necessary to minimize the growth of and kill Legionella bacteria has the potential to cause serious thermal shock and scalding injuries. As such, many plumbing engineers will specify that the water heater be set to maintain water temperatures at 140°F or higher to reduce the risk of Legionella, but then specify the appropriate mixing valve to ensure safe delivery of hot water to the fixtures. For a more thorough discussion of Legionella please go to here and the following link to the US Department of Labor OSHA information regarding Legionnaires’ Disease OSHA here

My question is not found in these FAQ’s, where do I look next?

Check out the Hubbell Product Center at Here for a complete listing of all technical documentation available by model. Get easy access to Installation, Operation & Maintenance manuals, Sales Brochures, Service Bulletins, Wiring Schematics, Parts Breakdowns and various other technical documents related to the full line of Hubbell water heaters. Or, if you prefer, please call us at 800-647-3165 and ask to speak to a Sales Engineer.

Downloads

Many of our products literature is available online for download. To open these files, a PDF viewer is required. If you do not have one, Adobe provides Acrobat Reader free of charge for viewing only. Use this link to download Acrobat Reader. You may also choose to download the file to your PC for future reference or printing. On most operating systems, simply right-click on the links below, choose "Save target as..." or "Save link as...", choose a location and it will save the document to your computer for future reference.

Model STX Specific Questions

My question is not found in these FAQ’s, where do I look next?

Check out the Hubbell Product Center at Here for a complete listing of all technical documentation available by model. Get easy access to Installation, Operation & Maintenance manuals, Sales Brochures, Service Bulletins, Wiring Schematics, Parts Breakdowns and various other technical documents related to the full line of Hubbell water heaters. Or, if you prefer, please call us at 800-647-3165 and ask to speak to a Sales Engineer.

Where can I purchase replacement parts?

Parts are available for your Hubbell water heater direct from the factory. Please call 800-647-3165 and ask for our parts department. Please have your model and serial number handy.


For Further Assistance Please Contact a Hubbell Tech Support Rep.

Sam Wellington
samw@hubbellheaters.com
203-378-2659 x136
D.J. Dineson
djdineson@hubbellheaters.com
203-378-2659 x125
Hubbell Heaters
45 Seymour Street
P.O. Box 288
Stratford, CT 06615-0288
Tel: 203-378-2659
Fax: 203-378-3593
Product Center
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