Installation and Maintenance Manual

Maintenance
RTAE-SVX001B-EN 69
Recommended Maintenance
Weekly
While unit is running in stable conditions.
1. At AdaptiView™TD7 orTracer™TU service tool, check
pressure for evaporator, condenser and intermediate
oil.
2. Observe liquid line sight glass on EXV. If liquid line
sight glass has bubbles measure the subcooling
entering the EXV. Subcooling should always be greater
than 10°F.
3. Inspect the entire system for unusual operation.
4. Inspect the condenser coils for dirt and debris. If the
coils are dirty, See
“Condenser Coils — Cleaning and
Inspection,” p. 72.
Monthly
1. Perform all weekly maintenance procedures.
2. Record the system subcooling.
Annual
1. Perform all weekly and monthly procedures.
2. Check oil sump oil level while unit is off. See “Oil Sump
Level Check,” p. 69.
3. Perform pH test of drive cooling fluid. See “pHTest,”
p. 71.
4. Have a qualified laboratory perform a compressor oil
analysis to determine system moisture content and
acid level.
5. Contact aTrane service organization to leak test the
chiller, to check operating and safety controls, and to
inspect electrical components for deficiencies.
6. Clean and repaint any areas that show signs of
corrosion.
7. Clean the condenser coils. See “Condenser Coils —
Cleaning and Inspection,” p. 72.
Refrigerant and Oil Charge
Management
Proper oil and refrigerant charge is essential for proper
unit operation, unit performance, and environmental
protection. Only trained and licensed service personnel
should service the chiller.
Table 30 lists baseline measurements for Stealth 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 localTrane office.
Note: Low temperature applications units will have
values that vary from Table 30. Contact your local
Trane office for more information.
Lubrication System
The lubrication system has been designed to keep most of
the oil lines filled with oil as long as there is a proper oil
level in the oil sump.
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 off line.
3. Let the chiller sit (powered, but off line) 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.
NOTICE:
Equipment Damage!
Do not use detergents to clean RTAE coils. Use clean
water only. Use of detergents on RTAE coils could
cause damage to coils.
NOTICE:
Equipment Damage!
Do not use detergents to clean RTAE coils. Use clean
water only. Use of detergents on RTAE coils could
cause damage to coils.
Table 30. Typical Stealth baselines (AHRI conditions)
Measurement Baseline
Evaporator Pressure 51 psia
Evaporator Approach 3.4°F
EXV Position (150-200T units) 45-50% open
EXV Position (225-300T units) 61-64% open
Evaporator delta T - entering 54°F
Evaporator delta T - leaving 44°F
Discharge Superheat 16.5°F
Condenser Pressure 212 psia
Subcooling 10-20°F