McQuay WGS130AA: WGS140AW, Руководство по эксплуатации

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OM WGS-5 WGS 130A to 190A 5
Evap Recirc Timer
A timing function, with a 30-second default, that holds off any reading of chilled water for
the duration of the timing setting. This delay allows the chilled water sensors (especially
water temperatures) to take a more accurate reading of the chilled water system conditions.
EXV
Electronic expansion valve, used to control the flow of refrigerant to the evaporator,
controlled by the circuit microprocessor.
High Saturated Condenser – Hold Value
High Cond Hold Value = Max Saturated Condenser Value – 5

F
This function prevents the compressor from loading whenever the pressures approach
within 5 degrees of the maximum discharge pressure. The purpose is to keep the
compressor online during periods of possibly temporary elevated pressures.
High Saturated Condenser – Unload Value
High Cond Unload Value = Max Saturated Condenser Value – 3

F
This function unloads the compressor whenever the pressures approach within 3 degrees of
the maximum discharge pressure. The purpose is to keep the compressor online during
periods of possibly temporary elevated pressures.
High Superheat Error
The degrees of temperature difference between 40

F and the actual discharge temperature.
Light load Stg Dn Point
The percent load point at which one of two operating compressors will shut off, transferring
the unit load to the remaining compressor.
Load Limit
An external signal from the keypad, the BAS or a 4-20 ma signal that limits the compressor
loading to a designated percent of full load. Frequently used to limit unit power input.
Load Balance
Load balance is a technique that equally distributes the total unit load among the running
compressors.
Low Ambient Lockout
Prevents the unit from operating (or starting) at ambient temperatures below the setpoint.
Low Pressure Hold Setpoint
The psi evaporator pressure setting at which the controller will not allow further compressor
loading.
Low/High Superheat Error
The difference between actual evaporator superheat and the superheat target.
LWT
Leaving water temperature. The “water” is any fluid used in the chiller circuit.