Trane CVGF-SVU02B-E4 Operation And Maintenance Manual page 18

Oil Management
The primary purpose of Oil
Management is to ensure
appropriate and sufficient
lubrication to the bearings
during compressor operation
and to minimize refrigerant
dilution in the oil.
The Oil Management system
performs safety checks and
manages the operation of the Oil
Pump and the Oil Heater. The
sensor inputs used for these
purposes are the Differential Oil
Switch, and the Oil Temperature.
Two oil heater outputs exist, that
should always operate
simultaneously, for example,
both on or both off.
Note: The Oil Pump and the Oil
Heater are never energized at the
same time.
18
General
Information
Low Oil Temperature Start
Inhibit Setpoint default is: 95° F.
When enhanced oil protection is
enabled, the low oil temperature
start inhibit is the saturated
evaporator at 30°F (16.6°C) or
105°F (40.5°C), whichever is
higher.
When enhanced oil temperature
protection is enabled, the oil
temperature setpoint is fixed at
136°F (57.8°C).
The oil temperature control
setpoint range is settable from:
100 to 160°F (37.8 to 71.1°C)
Essential Modes
The Oil-Management has the
following modes:
1. Low Temperature Start Inhibit:
The oil temperature is at or
below the low oil temperature
start inhibit setpoint. The heater
is energized to raise the oil
temperature. See Low
Temperature Start Inhibit section
for information about Enhanced
Oil Temp Protection.
This mode is indicated to the
user.
2. Idle: The oil pump is off. The
oil temperature is maintained
by the heater, at the control-
temperature setpoint +/- 2.5°F
(1.4°C).
3. Pre-lube: The oil pump
lubricates the bearing for 30
seconds before the
compressor starts.
This mode is indicated to the
user.
4. Running: The oil pump
continues to lubricate the
bearings when the compressor
is running.
CVGF-SVU02B-E4