technology ensures reliable high performance at a low sound level over a wide range
of operating conditions.
66
Flow Switch Opening:
The flow switch is normally closed during pump operation. Should liquid solution flow be
interrupted for any reason the control will open shutting down and locking out the chiller operation. The only exception
to this is when power is first applied to the chiller and the pump bypass timer bypasses the flow switch for 10 seconds.
When the system is first filled with liquid solution and the pump is started, expect the system to cycle off on t
flow switch, until all of the air is removed from the piping system. The system will have to be reset by openin
and then closing the disconnect switch or circuit breaker powering the chiller.
Low Pressure Switch Opening: Should the compressor suction pressure go low enough (40 PSI) to open the low-
pressure switch, the compressor and condenser fan motors will shut down. Check for a refrigerant leak, inoperative
thermal expansion valve, low liquid solution control setting, low ambient operation, low liquid solution flow, etc.
High Pressure Switch Opening: Should the compressor discharge pressure go high enough to open the high- pressure
switch, the compressor and condenser fan motors will shut down. Check for a dirty condenser coil, inoperable fan motor(s)
or the recirculation of condenser air.
Refrigeration System Operation
The refrigeration system is a closed loop consisting of 1 compressor, single circuit heat exchanger (evaporator), metering
device (TXV) and condenser coil. The refrigerant circulated is R407c. Hot gas is pumped from the compressors to the
to the condenser coil where the two condenser fans pull cooler air across the coil condensing and sub cooling the refrigerant.
Description Of Refrigerant Components
The now liquid refrigerant flows through the liquid line to the thermal expansion valves, where the refrigerant pressure
drops causing the refrigerant to boil at a much lower temperature (34-40°F). The refrigerant leaves the expansion valves and
swirls through the plates of the heat exchanger absorbing heat from the circulating liquid solution.
The evaporator or heat exchanger is designed to operate with an 8-10°F superheat. The condenser is designed to
condense the refrigerant and sub cool it to 10°F below condensing temperature.
Caution the top half of the scroll compressor operates at a temperature high
Scroll Compressor: All Multiaqua chillers feature Scroll compressors. Scroll
enough to cause serious injury.
SYSTEM FAULTS:
To Next Page
