Freeze Protection - Trane CGAM Installation & Operation Manual

Installation - Mechanical

Freeze Protection

Depending on the ambient temperature the unit may be exposed to there are up to four different
options for freeze protection. They are listed in order of highest ambient (least freeze protection)
to lowest ambient (most freeze protection).
5. Water pump (for protection with ambient temperatures down to 0°F)
OR
6. Heaters (for protection with ambient temperatures down to -20°F)
OR
7. Freeze inhibitor with heaters
OR
8. Drain water circuit (for protection with ambients below -20°F)
Note: By default the CH530 freeze protection control is enabled and will request the start of the
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a. CH530 controller can start the pump when the ambient temperatures drops to prevent
freezing. For this option the pump must to be controlled by the CGAM unit and this function
must be validated.
b. Water circuit valves need to stay open at all times.
a. Heaters are factory-installed on the evaporator and water piping and will protect them from
freezing in ambient temperatures down to -20°F (-29°C).
b. Install heat tape on all water piping, pumps, and other components that may be damaged
if exposed to freezing temperatures. Heat tape must be designed for low ambient
temperature applications. Heat tape selection should be based on the lowest expected
ambient temperature.
a. For protection with ambient temperatures down to -20°F:
i. Add a freeze inhibitor fluid to the chilled water system. The solution must be strong
enough to provide protection against ice formation at the lowest anticipated ambient
temperature.
ii. Activate the heaters and heat tape on the unit.
b. For protection with ambient temperatures below -20°F:
i. Add a freeze inhibitor fluid sufficient for burst protection at the lowest anticipated
ambient temperature.
ii. Activate the heaters and heat tape on the unit.
Note: Use of a freeze inhibitor fluid reduces the cooling capacity of the unit and must be
considered in the design of the system specifications.
a. Shut off the power supply to the unit and to all heaters.
b. Purge the water circuit.
c. Blow out the evaporator to ensure no liquid is left in the evaporator.
chilled water pump with ambient temperatures less than the evaporator low leaving water
temperature setpoint. The pump remains ON until the minimum evaporator water
temperature is great than low leaving water temperature setpoint plus 7°C. The minimum
on time for the pump is 5 minutes. If you do NOT want the CH530 to start the pump when
the ambient temperature drops to freezing, disable this freeze protection control.
CG-SVX17D-EN