Severn Trent VAX4600 Series, Инструкция по эксплуатации

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115.6001.10 - 14 -
b. Install the pressure reducing valve as shown in Bulletins 115.6010, 115.3002 and Figure 6.
NOTE : The pressure reducing valve must be located as close as possible to the gas discharge of
the vaporizer.
The outlet of the reducing valve should be routed to the process equipment. A 1/4" vent pipe
(Schedule 80 seamless steel or forged steel conforming to ASTM A-105 and A-106, Grade B)
should terminate outdoors in an area that can tolerate gas discharge. DO NOT MANIFOLD
VENT LINES. Position piping so it will not collect foreign matter or water. A screen over the
discharge of the vent line is recommended to prevent clogging.
c. An optional pressure switch set to actuate at 200 psig (1380 kPa/13.8 bar) may be installed in the
gas line between the vaporizer discharge and the pressure relief valve assembly. This will act as
an early warning of an over pressure condition to prevent relief valve venting. See Figure 6.
2.3.2 Liquid Line Connections
a. Install a 1" liquid inlet shutoff valve just prior to the vaporizer inlet ammonia union. An expansion
chamber with rupture disc must be installed upstream of the shutoff valve. (See Figure 6)
Additional expansion chambers must be installed in any lengths of liquid piping if they are
between shutoff valves. All expansion chambers should have a capacity of at least 20% of the
line volume which they protect and should be mounted at the highest point of the liquid line.
Refer to Bulletin 115.6020 for optional configurations.
b. Route 1" pipe from the liquid inlet shutoff valve to the chemical source. (See Figure 7)
c. Install a flexible connector on the 1" pipe. Attach an isolating valve on the free end of the flexible
connector and connect to the liquid valve of the chemical container.
2.3.3 Water Line Connections (See Figure 6)
a. Install 1" overflow piping to the outlet provided on the top of the hot water tank. Route to drain. In
order to fit the tank cover on the vaporizer, the overflow pipe must be run straight down the back
of the water bath and exit at the top of the bottom opening on the back cover.
b. Connect 1" unrestricted vent pipe from the tee.
c. Connect 1/2" drain and fill pipe to the outlet provided at the base of the water tank header box.
Install a 1/2" gate valve in the drain line.
d. Install a 1/2" gate valve in line for manual filling. For automatic filling, a 1/2" solenoid valve is
supplied. Keep the manual valve closed at this time.
e. A 10 psig (70 kPa/0.7 bar) minimum potable water inlet must be provided to the filling valve.
f. Install a 4 gpm (15 l/m) flow control valve (noting the direction of flow) in the water fill piping.
2.4 Wiring
CAUTION: Keep electrical power OFF while working on electrical equipment. Do not apply electrical power
directly to the heater circuit without water in the tank as damage will result.
Wire all components per Bulletins 115.3020 or 115.3021. Be sure any connected alarm devices do not
exceed maximum power limitations.
NOTE : All wiring must be in accordance with local codes and regulations. Refer to the NATIONAL
ELECTRICAL CODE (NFPA-70, ARTICLE 500) for special wiring requirements when feeding ammonia.
Refer to Figure 8 for specific locations of terminals and water and heater control components.
2.4.1 Heater Circuit
a. The magnetic contactor, if not cabinet mounted, must be installed on a suitable wall or electric
panel and wired to the heater terminal strip (A-B-C). Refer to the manufacturer’s instruction
manual. A contactor mounted on the vaporizer tank is pre-wired.