Maintenance
RTAF-SVX001A-EN
63
Refrigerant and Oil
Charge Management
Proper oil and refrigerant charge is essential for proper
unit operation, unit performances, and environmental
protection. Only trained and licensed service personnel
should service the chiller.
Table 24
lists baseline measurements for Sintesis™ units
running at AHRI standard operating conditions. If chiller
measurements vary significantly from values listed below,
problems may exist with refrigerant and oil charge levels.
Contact your local Trane office.
Note:
Low temperature applications units will have
values that vary from
Table 24
. Contact your local
Trane office for more information.
Lubrication System
Oil Sump Level Check
The oil level in the sump can be measured to give an
indication of the system oil charge. Follow the procedures
below to measure the level.
1.
Run the unit as near to full load as possible for a
minimum of 30 minutes. For an accurate reading, 40 or
more minutes at full load with normal/steady
discharge superheat readings and no limits/warnings
is recommended. Assessing oil charge after running at
minimum or low loads may lead to an inaccurate
reading.
2. Cycle the compressor offline.
3. Let the chiller sit (powered, but offline) to allow the oil
separator heater to boil off the refrigerant that may be
in the oil separator. An initial assessment of the oil
separator level may be made after 30 minutes of heater
ON dwell time, but oil charge adjustments should not
be made without allowing the oil heaters to run for a
minimum of 4 hours.
Table 24.
Typical Sintesis baselines (AHRI conditions)
Measurement
Baseline
Evaporator Pressure
50.5 psia
Evaporator Approach
3°F
EXV Position
45% open
Evaporator Fluid delta T - entering
54°F
Evaporator Fluid delta T - leaving
44°F
Discharge Superheat
25°F
Condenser Pressure
195 psia
Subcooling
18°F
Figure 53.
Oil sump level check
1
Oil Separator
3
Refrigeration hose
2
Valves
4
Sight Glass
2
1
3
4
Oil Level
2