Hubbell CR User Manual
5
SECTION I -
GENERAL DESCRIPTION AND CONSTRUCTION
GENERAL DESCRIPTION
This book describes a packaged electric heater that is a stationary, self-contained unit. The complete
assembly consists of the pressure vessel, immersion electric heating element, thermostat, safety relief
valve, safety high temperature cut out, magnetic contactor(s), power circuit fusing, fused low voltage
control circuit transformer, and any other required electrical operating control. Optional equipment may
be supplied with your unit. Please consult the product drawing for details specific to your assembly.
The unit is factory assembled, insulated, jacketed, wired, tested, and ready for electrical and plumbing
service connections.
assembly consists of the pressure vessel, immersion electric heating element, thermostat, safety relief
valve, safety high temperature cut out, magnetic contactor(s), power circuit fusing, fused low voltage
control circuit transformer, and any other required electrical operating control. Optional equipment may
be supplied with your unit. Please consult the product drawing for details specific to your assembly.
The unit is factory assembled, insulated, jacketed, wired, tested, and ready for electrical and plumbing
service connections.
CONSTRUCTION
PRESSURE VESSEL
Standard Vessel Construction:
The standard pressure vessel is constructed of all welded carbon steel, then hot dip galvanized for
added corrosion resistance. Units over 58 kW are designed and built in accordance with ASME Section
IV and stamped, certified, and registered with the National Board of Boiler and Pressure Vessel
Inspectors. The maximum allowable working pressure is stamped on the nameplate. The standard
working pressure is 150 psi (225 psi TP).
Optional Non-Ferrous Vessel Materials:
Standard Vessel Construction:
The standard pressure vessel is constructed of all welded carbon steel, then hot dip galvanized for
added corrosion resistance. Units over 58 kW are designed and built in accordance with ASME Section
IV and stamped, certified, and registered with the National Board of Boiler and Pressure Vessel
Inspectors. The maximum allowable working pressure is stamped on the nameplate. The standard
working pressure is 150 psi (225 psi TP).
Optional Non-Ferrous Vessel Materials:
1. Copper-Silicon – A copper-silicon alloy offers tremendous longevity due to its ability to
withstand the cycling effects induced from changes in water temperature and pressure. This
material is suitable for storage of hot potable water in a variety of commercial and industrial
applications.
material is suitable for storage of hot potable water in a variety of commercial and industrial
applications.
2. 90/10 Copper-Nickel – A 90% copper and 10% nickel alloy similar to copper-silicon, but with
added strength and corrosion resistance. Typically used in applications with corrosive
environments (salt water) or critical applications.
environments (salt water) or critical applications.
3. Stainless Steel – Stainless steel (type 304, 316, or 316L) is well suited for high purity
applications requiring a corrosion resistant tank with minimal leaching of impurities into the
water. Well suited for process, RO, and DI water systems in the pharmaceutical, food, and
electronic industries.
water. Well suited for process, RO, and DI water systems in the pharmaceutical, food, and
electronic industries.
4. Other materials are available upon request.
Optional Working Pressures:
The pressure vessel may be supplied with optional working pressures (standard working pressure is 150
psi). See drawing for details.
VESSEL CONNECTIONS
The heater is supplied with separate cold water and hot water connections. A connection is provided for
mounting a combination safety temperature and pressure relief valve. An overflow line should be
utilized from the relief valve outlet to a floor drain. See drawing for locations and sizes.