Dunham-Bush ACDX, Installation, Operation And Maintenance Instructions

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4.22 High Motor Temperature Safety 4.24 High Discharge Pressure Unload
If the high motor temperature switch of a This function unloads the compressor if
compressor opens, the motor temperature discharge pressure is approaching the high
digital input turns ON. If the compressor is pressure limit. If discharge pressure of an
operating, the compressor will be locked off. operating compressor reaches the high
The high motor temperature alarm will be pressure setpoint minus 10 psi, the
recorded by the computer and RESET must compressor will be prevented from loading
be pressed after the problem is resolved. (HOLD state). If the discharge pressure
4.23 Low Chiller Flow Alarm
A low flow alarm will be generated if a
compressor control point is ON and the flow
switch digital input is OFF. All compressors
This function unloads the compressor if suction
will be locked off and the alarm light turned pressure is approaching the low pressure limit.
on. After resolving the problem, press If suction pressure reaches the low pressure
RESET. setpoint plus 4 psi, the compressor will be
reaches the high pressure setpoint minus 5
psi, the compressor will begin unloading.
4.25 Low Suction Pressure Unload
prevented from loading (HOLD state). If
suction pressure falls to the suction pressure
setpoint plus 2 psi, the compressor will begin
unloading.
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