York YVAA Installation Operation & Maintenance page 176

SECTION 9 - MAINTENANCE
Before applying power to the chiller, ensure
the chilled liquid system is filled
DO NOT apply power to the chiller unless
the system is filled with water or glycol. If
the chiller is equipped with the -20°F op-
tion, applying power to an empty chilled
liquid system will cause the evaporator
immersion heaters to fail.
Removing water/glycol from the evaporator
If the chiller is equipped with a -20°F
evaporator freeze protection option, which
incorporates immersion heaters, power
must be removed from the chiller before
the evaporator is drained to ensure that
the heaters are not damaged. Failure to
remove power will cause the evaporator
immersion heaters to fail.
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Evaporator freeze damage
Power must remain on the chiller when-
ever the ambient temperature drops below
32°F with water in the evaporator to avoid
evaporator damage. To avoid damage,
ensure that the correct heater option for
0°F minimum ambient or -20°F minimum
ambient temperature is installed, based on
the lowest expected ambient temperature
at the chiller location.
During operation, the glycol freeze point
must also be below the lowest expected
refrigerant temperature.
Glycol concentration
If glycol is used in the evaporator, the
glycol concentration must ensure that the
freeze point is below the lowest expected
ambient temperature at the chiller loca-
tion to avoid evaporator damage.
Winterization
If glycol is used in the evaporator, the
glycol concentration must ensure that the
freeze point is below the lowest expected
ambient temperature at the chiller loca-
tion to avoid evaporator damage.
Form 201.47-ICOM1
Issue date: 17/11/2022
JOHNSON CONTROLS