Carrier 17/19EX - Manual (Page 86)

Oil Cooler
The oil must be cooled when the compressor is running.
EX Compressors: This is accomplished through a small, plate-type heat exchanger. The heat
exchanger uses liquid condenser refrigerant as the cooling liquid. A refrigerant thermostatic
expansion valve (TXV) regulates refrigerant flow to control oil temperature entering the
bearings. There is always a flow of refrigerant bypassing the TXV. The bulb for the expansion
valve is strapped to the oil supply line leaving the heat exchanger and the valve is set to
maintain 110 F (43 C).
Note: The expansion valve is not adjustable. Oil sump temperature may be at a lower tempera-
ture.
FA Compressors: The oil cooler is a water cooled, tube-in-shell type heat exchanger. A plug
valve is manually set to maintain proper temperatures. Set the valve to maintain 145 F (63 C) oil
sump temperatures while the compressor is running.
Remote Start/Stop Controls
A remote device, such as a timeclock which uses a set of contacts, may be used to start and
stop the machine. However, the device should not be programmed to start and stop the
machine in excess of 2 or 3 times every 12 hours. If more than 8 starts in 12 hours occur, then
an Excessive Starts alarm is displayed, preventing the machine from starting. The operator
must reset the alarm at the LID in order to override the starts counter and start the machine. If