Johnson Controls YEWS Series User Manual

Instructions for capacity control (AC mode for example)
Ts： Leaving chilled water temperature setpoint (LEL TEMP SET )
D： Differential of Leaving chilled water temperature (LEL TEMP CR)
Db：Differential buffering value
When leaving chilled water temperature ≥(Ts + D), the compressor will load. when leaving chilled water
temperature ≥(Ts - D) and≤(Ts + D) , the comrepssor will operate fuzzy control logic. when leaving chilled
water temperature ≥(Ts – D- Db) and≤(Ts - D) , the comrepssor will unload. When leaving chilled water
temperature ≤(Ts – D- Db) , the compressor will be cycling shut down.
By setting the value of Ts, D and Db, the temperature range of different running
mode(Hold/Unload/Load/Stop) of compressor can be adjusted.
Loading
Holding
Unloading
Emergency Stop
Low
temperature
High
temperature
Ts+D
Ts
Ts-D
Ts-D-Db
YEWS-E Water Cooling Screw Chiller/Heat Pump
32

Johnson Controls YEWS Series Specifications

General

Brand	Johnson Controls
Model	YEWS Series
Category	Chiller
Language	English