Trane RTAC 140-500 ton units (60 Hz) User Manual

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RTAC-SVX01F-EN
161
Maintenance Procedures
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.
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: 
Table 38
Oil Charging Data
Circuit
(Tons)
Approximate sump oil level after 
running “normal” conditions
(in)
Normal quantity of oil in refrigera-
tion system (evaporator/condenser) 
lb (gal)
70
7
1.1 (0.14)
85
6
1.1 (0.14)
100
7
1.8 (0.23)
120
7
1.8 (0.23)
170
8
3.5 (0.44)
200
8
3.5 (0.44)
240
8
3.5 (0.44)