Carrier 17/19EX - Manual (Page 44)

always a minimum flow bypassing the TXV, which flows through an orifice. The TXV valve
regulates flow into the oil/refrigerant plate and frame-type heat exchanger. The bulb for the
expansion valve controls oil temperature to the bearings. The refrigerant leaving the heat
exchanger then returns to the cooler.
On machines with FA compressors, the oil is water cooled. Water flow through the oil cooler
is manually adjusted by a plug valve to maintain an operating temperature at the reservoir of
approximately 145 F (63 C).
Hermetic Machines (19 Series) Lubrication Cycle
Summary
The compressor oil pump and oil reservoir are located in the compressor base. Oil is pumped
through an oil cooler and a filter to remove heat and any foreign particles. Part of the oil flow is
directed to the compressor motor-end bearings and seal. The remaining flow lubricates the
compressor transmission, thrust and journal bearings and seal. Oil is then returned to the
reservoir to complete the cycle ( Figure 5 ).
Click here for Figure 4 — Refrigerant, Motor Cooling, and Oil Cooling Cycles