Hubbell ST, Руководство по эксплуатации и техническому обслуживанию

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OUTER SHELL, INSULATION, AND SUPPORTS
The tank is encapsulated in 2-inches of high-density fiberglass insulation. The protective
shell is constructed of galvaneel and is coated with a durable silver hammertone finish.
The entire vessel is supported on heavy-duty integrally welded steel supports for sturdy
floor mounting.
STEAM HEATING COIL
The water heater is supplied with a high quality factory installed 2-pass U-tube heating
coil constructed from 20-gauge ¾-inch O.D. single wall copper tubing designed for a
maximum working pressure of 150 psi. The tubing is installed in a heavy-duty fabricated
steel head with threaded NPT steam and condensate connections. Each assembly is
fastened to a corresponding tank flange
using a gasket and hex head steel bolts
and nuts. Specialized heating coil
construction may be included. These
options include: double wall tubing with a
leak detection port, or special materials
(stainless steel, 90/10 copper-nickel,
other) for the tubes and/or head. See
drawing for complete details.
STEAM OPERATING CONTROLS
The steam operating controls are factory selected, sized, piped, and tested to ensure
reliable operation. Steam controls can be shipped loose, upon request, for in the field
installation by others. All steam components are factory plumbed with schedule 40
black iron pipe and ready for steam and condensate connections. A cast iron ‘Y’
strainer with 20 mesh screen protects the steam controls and coil from dirt and debris
in the steam supply.
Traps
Two traps should be utilized in the immediate steam piping system of the water heater.
The first trap in the system is a drip trap that is designed to collect condensate from the
main steam line before entering the steam regulator. Additionally, a main condensate trap
should be located in the condensate line after the steam coil. This trap ensures that the
steam remains in the coil and releases its energy before exiting the coil and traveling
down the condensate line. There are various types of traps available. The following may
be included in your water heater package:
1. Drip Trap
a. Thermostatic (Standard)
b. Cast Iron Float and Thermostatic type
c. Cast Steel Float and Thermostatic type
2. Main Trap
a. Cast Iron Float and Thermostatic type (Standard)
b. Cast Steel Float and Thermostatic type
c. Bucket
Steam Control Valves
1. Pilot Operated (Standard) – A high quality cast iron pilot operated steam
control valve comes with the standard unit. It is the most widely used type of
valve for water heating applications. In this type of valve, a temperature pilot
device utilizes steam to operate the main valve. No external power source is
required other than steam. This highly dependable temperature control system is
suitable for most commercial and industrial applications.
2. Self Operating – This valve design includes a bulb and capillary assembly
charged with a thermally responsive vapor. The expansion / contraction of the
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