Nomenclature - Emerson Copeland 4MF-13X User Manual

Oil Circulation
Oil returns with the suction gases through a suction strainer and separates in the motor chamber reaching the crankcase by way of oil
return relief valve in the partition between motor housing and crankcase. This relief valve closes on compressor start-up due to the
pressure difference arising between motor side and crankcase, thus, slowing down pressure decrease in the crankcase over a certain
period of time. It reduces the foaming of the oil/refrigerant mixture that would occur if the pressure decreased rapidly. The valve does
not reopen until the pressure has been equalized by means of a crankcase ventilating valve. This second valve connects the crankcase
and suction side cylinder head. It reduces the pressure difference by means of a very small bore in the plate of the valve so slowly that oil
foams less and only limited oil/refrigerant foam is transferred to the oil pump.
Four-cylinder compressors have one crankcase ventilating valve on the left cylinder bank, whereas, six-cylinder compressors have two
ventilating valves on the left and right cylinder banks.
Oil level
All compressors are delivered with sufficient oil for normal operation (see Table 2). The optimum oil level should be checked by operat-
ing the compressor until the system is stable and then comparing the sight glass reading with the appropriate diagram below. Oil level
should be min 1/4 and max 3/4 of sight glass.
For service compressors when an oil regulator is used the oil level should be min 1/4 and max 3/4 of sight glass. The level can also be
checked within 10 seconds of compressor shut-down.
For 4M* and 6M* compressors, a higher oil level may be accepted when an oil regulator is in use because the oil separator will reduce
excessive oil circulation.

Nomenclature

D - Digital
Family
M - Copeland Stream
4 M H D 1 - 25X - AWM/D - D000
Number
of Cylinders
Bore Denomination
Figure 2: 4M* and 6M* compressors
Motor Size
25 = 25HP
Oil Type
X - Ester Oil
0 - Mineral Oil
Design Revision
Stream
3/4
1/4
Motor Code
Bill of Material
7