Johnson Controls York YHAU-C, Инструкция по установке, эксплуатации и обслуживанию

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• The critical load change condition to prevent an overcooling trip of the chiller is 5% / minimum
maximum.
Set the steam feed pressure at the inlet of the steam control valve to the specified level. If the
pressure is lower than the specification, the result is insufficient performance. Limit the steam
pressure fluctuation in the range of the specification value +7/-14 psig. If the pressure fluctuation
is too big, control becomes unstable. The valve seeks the correct chilled water temperature at the
outlet. As a result, the performance suffers and the operation can stop.
Install a 60 ~ 70 mesh strainer in front of the shut-off valve.
Use the regulator valve on the facility side to adjust the pressure at the steam drain outlet to match
the specification.
If air or steam flows back while the chiller is stopped, install a check valve in the middle of the drain
return piping.
If two or more chillers are installed and their drain return pipes are joined to return the drain to the
hot well tank, install the check valve before the junction of the pipes.
To prevent an inflow of drain liquid to the generator, install a drain trap at the lowest point of the
control valve inlet side.
If there is too much mist in the steam, install a mist separator.
A drain trap does not need to be installed in the steam drain line between the chiller and the hot
well tank. The condensed water draining from the chiller is sub-cooled enough that a drain trap is
unnecessary.
Isolate the main steam supply valve when you service the chiller or there is an extended shut down.
Chilled water outlet temperature controller
The chilled water outlet temperature controller is located on the sequencer and controls the chilled
water outlet temperature.
Liquid level gauges
Liquid level gauges are used to check the condition of the chiller components.
Table 22: Liquid level gauges
Liquid level gauge name Symbol Function
Refrigerant overflow monitoring level gauge G101 Checks refrigerant overflow level
Refrigerant tank level gauge G102 Checks lower limit of refrigerant tank level
Absorber level gauge G103 Checks lower limit of absorber
Generator level gauge G104 Checks condition of solution in generator
Starting the chiller
Before starting the chiller, inspect the following items:
• Check that the refrigerant blow valve (V8) is closed.
• Check the degree of the vacuum in the machine. Use the pressure gauge of the generator.
• Check that the steam supply valve is open.
• Open the steam shut off valve.
• Keep the steam inlet pressure at the specification.
• Check that the Refrigerant Pump Auto button is pressed.
99 YHAU-C Single Effect Steam-Fired Absorption Chiller