Factory (Initial) Oil Charging Procedure; Field Oil Charging Procedure - Trane R Series Installation, Operation And Maintenance Manual

Maintenance
Table 65. Oil charging data
Approximate sump oil
level after running
Circuit "normal" conditions
(Tons) (in)
70 7
85 6
100 7
120 7
170 8
200 8
240 8
1. To measure oil level, use the oil drain valve on the oil
line and a service valve on the discharge line.This
measurement can only be made when the circuit is not
running.
Note: The level is measured from the bottom of the
separator and 1" must be subtracted for the
thickness of the bottom plate.
2. The initial oil charge should be approximately at the
level in the above chart.This is the approximate oil
level if all the oil is in the oil lines, filter and oil sump
and the unit is in vacuum so that there is no refrigerant
dissolved in the oil.
3. After the unit has run for a while, the oil level in the
sump can vary greatly. However, if the unit has run
"normal" conditions for a long time the level should
resemble the level in the above chart. (+1" to – 4" (25
to -101mm) is acceptable.)
The field charging procedure depends on the
circumstances that resulted in the need for oil charge.
1. Some service procedures may result in loss of small
quantities of oil which must be replaced (oil analysis,
filter replacement, re-tubing the evaporator, etc.).
2. Additionally, some maintenance procedures may
result in virtually all of the oil being removed
(compressor motor burn or total removal of the charge
to trouble shoot a unit).
3. Finally, leaks may result in a loss of oil that must be
replaced.

Factory (initial) Oil Charging Procedure

The initial charging procedure should be followed any
time the unit is new or has had all of the oil removed.
4. If the isolation valves is closed, then the charge may be
trapped in the evaporator. In either case, the high side
of the system should not be pressurized.
5. The oil line shut off valve must be open to allow the oil
to pass into the oil lines and the oil separator.
RTAC-SVX01J-EN
Normal quantity of oil in
refrigeration system
(evaporator/
condenser)
lb (gal)
1.1 (0.14)
1.1 (0.14)
1.8 (0.23)
1.8 (0.23)
3.5 (0.44)
3.5 (0.44)
3.5 (0.44)
6. The oil charging port is a ¼" (6mm) flare fitting with a
schrader valve that is on the side of the oil filter
housing.This is the port that must be used to add oil
into the compressor so that the filter and lines are full
at the first start of the compressor.
7. On single compressor circuits all the oil should be put
into the circuit through the oil charging port on the
compressor filter housing. On two compressor circuits
put approximately ½ of the oil into the unit through
each of the two oil charging ports on the two
compressors.
8. Oil may be put into the unit using either of two
methods:
• Have the unit in vacuum. Note that the vacuum
connection should be made on the unit at the
service valve that is on the discharge line. Hook up
the oil charging hose to the oil charging fitting and
submerse the other end into the oil container. Let
the vacuum draw the required amount of oil into the
unit.
• Have the unit at the same pressure as the oil. Hook
up the oil charging hose to the oil charging fitting
and the other end to an oil pump. Use the pump to
draw oil out of the oil container and push the
required amount of oil into the unit.
Note: The compressor filter has an internal shut off valve
that will prevent oil from entering the compressor
while the compressor is not running.Therefore,
there is no concern about flooding the compressor
with oil.
NOTICE:
Equipment Damage!
Use only Trane OIL00048 in the RTAC units to avoid any
catastrophic damage to the compressor or unit.

Field Oil Charging Procedure

Use the initial charging procedure under the following
circumstances:
• When virtually all of the oil has been removed.
• If the oil charge is removed from the compressor and
oil system only but the unit has been run for less than
15 minutes.
• If the oil charge is removed from the compressor and
oil system only and the unit has been run for more than
15 minutes. However, reduce the amount of oil added
to the unit by the normal quantity of oil in refrigeration
system.
Note: This procedure can be followed even with the
refrigerant charge isolated in the evaporating
section of the unit.
If small quantities of oil were removed to service
refrigeration components, such as the evaporator,
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