Installation and Maintenance Manual

Service and Maintenance
RLC-SVX09H-EN 189
significantly higher temperature than the ambient outdoor
air temperature (5 ºF or more).
All of the fans should also be validated to be operational
with the proper fan blade rotation direction. Dirty, or
fouled coils, or otherwise limited or restricted air flow
through the coils, can significantly degrade the efficiency
of the chiller as well as result in unnecessary limits and
nuisance trips. Refer to the condenser manufacturers’
maintenance and cleaning procedures.
Cleaning the Evaporator
Since the evaporator is typically part of a closed circuit, it
does not accumulate appreciable amounts of scale or
sludge. However, if cleaning is deemed necessary, use the
same cleaning methods described for the condenser
tubes.
Compressor Oil
Trane Polyolester Oil is the approved oil for the RTWD/
RTUD units. Polyolester oil is extremely hygroscopic
meaning it readily attracts moisture.The oil can not be
stored in plastic containers due to the hygroscopic
properties. As with mineral oil, if water is in the system it
will react with the oil to form acids. UseTable 132 to
determine the acceptability of the oil.
Note: Use an oil transfer pump to change the oil
regardless of chiller pressure.
Oil Sump Level Check
Running the chiller at minimum load is the best for the
quickest return of oil to the separator and sump.The
machine still needs to sit for approximately 30 minutes
before the level is taken. At minimum load, the discharge
superheat should be highest.The more heat in the oil as it
lays in the sump, the more refrigerant will boil off in the
sump and leave more concentrated oil.
The oil level in the oil 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 fully unloaded for approximately 20
minutes.
2. Cycle the compressor off line.
3. Attach a 3/8” or 1/2” hose with a sightglass in the
middle to the oil sump service valve (1/4” flare) and the
oil separator service valve (1/4” flare).
Note: Using high pressure rated clear hose with
appropriate fittings can help speed up the process.
4. After the unit is off line for 30 minutes, move the
sightglass along the side of the oil sump.
5. The level should be between 4” and 9.5” from the
bottom of the oil sump. If the level appears to be above
9.5”, the oil sump is completely full. Most likely more oil
resides in the rest of the system and some oil needs to
be removed until the level falls between 4” and 9.5” in
the oil sump.
Note: Nominal height of oil is 8 inches.
NOTICE:
Equipment Damage!
To prevent oil sump heater burnout, open the unit
main power disconnect switch before removing
oil from the compressor.
Table 132. POE Oil Properties
Description Acceptable Levels
Moisture content less than 300 ppm
Acid Level less than 0.5 TAN (mg KOH/g)
Note: Mineral oil used in the RTHA and RTHB units has different acceptable
levels (< 50 ppm of moisture and < 0.05 mg KOH/g)
NOTICE:
Equipment Damage!
Never operate the compressor with the sight glass
service valves opened. Severe oil loss will occur. Close
the valves after checking the oil level. The sump is
above the condenser and it is possible to drain the oil.
Figure 87. Determining oil level in the sump
service valve
Oil separator
4 “- 9.5”
Oil sump
service valve