© 2013 Pentair Equipment Protection
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TEMPERATURE CONTROL
The electromechanical thermostat is factory preset to 75 F/23 C. To change the temperature setting, remove the
front cover. Use a standard screwdriver to adjust thermostat. For cooler temperatures turn clockwise, for warmer
temperatures turn counterclockwise.
WATER USAGE
CONDENSER
The water cooled air conditioner uses water as the cooling medium for the condensing side of the hermetic
refrigeration system. This water is passed through a heat exchanger that uses the cool water to lower the
temperature of the hot gaseous refrigerant, causing it to condense. The water is warmed by this exchange of
heat, and is passed out of the air conditioner at an elevated temperature. The inlet and outlet water fittings are
located on the bottom of the air conditioner. A sealant is recommended when connecting the inlet and outlet
water lines to prevent leakage. It is extremely important for the air conditioner to have an uninterrupted supply of
clean cooling water. Interference with the water supply will cause the unit to automatically shut down and require
manual reset.
MANUAL RESET HIGH PRESSURE LIMIT SWITCH
The manual reset high pressure limit switch is located behind the front cover. This limit switch interrupts
compressor operation when condenser refrigerant exceeds 310 PSIG, which most frequently occurs as a result
of the condenser water supply being reduced or shut down. After identifying and correcting the problem with the
water supply to the unit, compressor operation can be restored by pushing the manual reset button located on the
switch.
WATER VALVE
The valve that controls the flow of condensing water is also located behind the front cover. This valve modulates
the flow of water to the condensing coil. Water flow varies according to a variety of loading conditions, including
electrical load, inlet water temperature, ambient air temperature, cabinet construction, etc. The maximum
flow rate in the Design Data on page 4 is given for the conditions of maximum rated load, maximum water
temperature, and maximum ambient temperature, and reflects the highest flow rate anticipated for the unit.
NOTE: This valve has been preset at the factory for the correct operation of the unit. The setting of the valve
should not be altered.
WATER
The air conditioner water supply does not require special treatment, but care should be taken to avoid any gross
contamination. Corrosives may cause leakage within the coil and water lines. Mineral rich water will cause
scaling of the coil, degrading performance. Particulates may cause rapid erosion of the coil, and could result in
clogging of the control valve. NOTE: A filter to clean the air conditioner water supply is recommended.
If the temperature of the inlet water is higher than that shown in the Design Data on page 4, it will result in a
higher flow rate, and may cause shut-down of the unit. High inlet water temperatures should be avoided.
When the air conditioner is shut-down, either because of a thermostatic cut-out or a loss of power, the water
flow should gradually diminish to zero. If water flow persists, it may indicate a malfunction of the control valve.
Information on the specific valve employed is supplied with the air conditioner.
