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Extended Unit Shutdown
The following procedure is to be followed if the system is to be taken out of service for an extended period
of time (i.e. seasonal shutdown):
1. Perform the normal unit stop sequence using the Stop key.
2. Open the electrical disconnect switches for the unit. Lock the switches in the “OPEN” position.
3. Remove evaporator power before draining evaporator to avoid heater burnout.
4. Open the electrical disconnect switches for the water pump. Lock the switches in the “OPEN” position.
5. Drain the chilled water system. Remove the drain and vent plugs from the evaporator waterbox to drain the
evaporator. Note: If unit downtime more than one month, recommend to fill low pressure nitrogen to avoid
pipe and evaporator shell corrosion.
6. Drain the heat recovery water system if installed.
7. At least every three months (quarterly), check the refrigerant pressure of the unit to verify the refrigerant
charge integrity.
NOTICE - Evaporator Heater Damage!
To prevent evaporator heater burnout, open the heater power disconnect switch before water
drain.
Seasonal Unit Start-up
Pass through the Unit Prestart checkup procedures 1~14, follow the Startup to start the unit.