Hubbell ST, Руководство по эксплуатации и техническому обслуживанию

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vapor acts upon the valve bellows in order to control the flow of steam through
the valve. No external power is required for operation.
3. Pneumatically Operated – In this configuration the building air supply feeds a
factory installed temperature controller that operates the steam control valve.
The temperature controller sends a precise air signal to the steam control valve
which adjusts the flow of steam into the heating coil. The temperature controller
is fully adjustable from 50° - 250 ° F and requires 20 psi air at a maximum
consumption of 0.5 SCFM.
4. Electronically Operated – This control valve is similar to a pneumatically
operated system, except in this case the temperature controller is a sophisticated
digital display electronic device which outputs a 4-20 ma signal to a compact
motor mounted on the steam control valve in order to proportionally control the
flow of steam to the heating coil. The temperature controller displays set point
as well as actual water temperature and is available with an RS485
communications port for remote control.
OPTIONS
The following optional features may be included in your water heater. Reference the
drawing specific to your heater for further details.
Single Solenoid Safety System
A single solenoid safety system closes the steam supply to the control valve should the
temperature in the tank reach the high limit set point. This option requires 120-volt, 5-
amp electrical service.
Double Solenoid Safety System
A double solenoid safety system dumps over heated water in the storage tank to drain
in addition to closing the steam supply to the control valve. This option requires 120-
volt, 5-amp electrical service.
Anticipator Control System
The anticipator control system forces incoming cold water over the control valve
sensing bulb in order to begin heating water immediately.
Skid Mounting
Optionally, the unit may be mounted on heavy duty all welded I-beams.
Circulating Pump Package
An intra-tank circulation pump package with On/Off switch to continuously circulate
water within the tank and thereby reduce stratification may be installed. An all bronze
circulator pump.
Dial Temperature and Pressure Gauge
A combination temperature (70° - 250° F) and pressure (0 – 200
psi) gauge with 2½-inch dial may be factory installed in the tank.
SECTION II –
INSTALLATION AND OPERATION
WARNING / CAUTION
DO NOT TURN ON THE STEAM SUPPLY to this unit until heater is completely
filled with water and all air has been released.
If the heater is NOT filled with water
when the steam supply is turned on, damage to the heating coil may result.
For protection against excessive pressures and temperatures, local codes require the
installation of a temperature-and-pressure (T&P) relief valve certified by a nationally
recognized laboratory that maintains periodic inspection of production of listed
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