30 YORK INTERNATIONAL
SYSTEM STARTING & SHUTDOWN SEQUENCE
OPERATOR INITIATED
LD01077
FIG. 15 – CODEPAK CHILLER STARTING SEQUENCE & SHUTDOWN SEQUENCE
However, the current draw (amperes) by the compres-
sor motor cannot exceed the setting of the % CUR-
RENT LIMIT at any time during the unit operation, since
the MicroComputer Control Center 40 to 100% three-
phase peak current limit software function, plus the 3-
phase 100% solid state overload current limiter (CM-
2) on Electro-Mechanical Starter applications or the
Solid State Starter current limit function will override
the temperature control function and prevent the Pre-
rotation Vanes from opening beyond the % CURRENT
LIMIT setting.
If the load continues to decrease, after the Prerotation
Vanes are entirely closed, the CodePak will be shut
down by the Low Water Temperature control (LWT)
function which is displayed on the Control Center as:
MON 10:30 AM – LOW WATER TEMPERATURE – AUTOSTART
This occurs when the leaving water temperature falls
to 4°F (2.2°C) below setpoint or 36°F (2.2°C), which-
ever is higher. The LWT is part of the Micro Board.
NOTE: If the temperature setpoint has been repro-
grammed within the last 10 minutes, the LWT
cutout is 36°F (2.2°C) for 10 minutes.
Condenser Water Temperature Control
The YORK CodePak is designed to use less power by
taking advantage of lower than design temperatures
that are naturally produced by cooling towers through-
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