Trane RTAC 300 Series User Manual

105 RTAC-SVX002A-EN
XI-Maintenance Procedures
Refrigerant and Oil Charge Manage-
ment
Proper oil and refrigerant charge is es-
sential for proper unit operation, unit per-
formance, and environmental protection.
Only trained and licensed service per-
sonnal should service the chiller.
Some symptoms of a refrigerant un-
der-charged unit:
• Low subcooling
• Higher than normal discharge super-
heat
• Bubbles in EXV sight glass
• Low liquid level diagnostic
• Larger than normal evaporator ap-
proach temperatures (leaving water
temperature
- saturated evaporator temperature)
• Low evaporator refrigerant tempera-
ture limit
• Low refrigerant temperature cutout di-
agnostic
• Fully open expansion valve
• Possible whistling sound coming from
liquid line (due to high vapor velocity)
• High condenser + subcooler pressure
drop
Some symptoms of a refrigerant over-
charged unit:
• High subcooling
• Evaporator liquid level higher than cen-
terline after shut down
• Larger than normal condenser ap-
proach temperatures (entering condens-
er saturated temperature – entering air
temperature)
• Condenser pressure limit
• High pressure cutout diagnostic
• More than normal number of fans run-
ning
• Erratic fan control
• Higher than normal compressor power
• Very low discharge superheat at startup
• Compressor rattle or grinding sound at
startup
Some symptoms of an oil over-
charged unit:
• Larger than normal evaporator ap-
proach temperatures (leaving water
temperature
- saturated evaporator temperature)
• Low evaporator refrigerant tempera-
ture limit
• Erratic liquid level control
• Low unit capacity
• Low discharge superheat (especially at
high loads)
• Low liquid level diagnostics
• High oil sump level after normal shut
down
Some symptoms of an oil under-
charged unit:
• Compressor rattle or grinding sound
• Lower than normal pressure drop
through oil system
• Seized or welded compressors
• Low oil sump level after normal shut
down
• Lower than normal oil concentrations
in evaporator
R134a Field Charging Procedure
Be certain that the electrical power to the
unit is disconnected before performing
this procedure.
WARNING
Hazardous Voltage w/Capacitors!
Disconnect all electric power, includ-
ing remote disconnects before ser-
vicing. Follow proper lockout/tagout
procedures to ensure the power can-
not be inadvertently energized. For
variable frequency drives or other
energy storing components provided
by Trane or others, refer to the appro-
priate manufacturer’s literature for al-
lowable waiting periods for discharge
of capacitors. Verify with an appropri-
ate voltmeter that all capacitors have
discharged. Failure to disconnect
power and discharge capacitors be-
fore servicing could result in death or
serious injury.
Note: For additional information re-
garding the safe discharge of capaci-
tors.
Factory (initial) Refrigerant Charging
Procedure
The initial charging procedure should be
followed the rst time the unit is charged
in the factory, as well as for charging
any time after the charge has been com-
pletely removed from the entire system
in the event of repair.
1. As part of automatic vacuum/charge
procedure, verify that the EXVs are
OPEN.
2. Attach vacuum hoses to evaporator
service valves (one per circuit). Open
service valves.
3. Attach charging hoses to the charg-
ing port on the liquid line lter (one per
circuit).
The lters contain a port with a ¼” (6mm)
are.

Trane RTAC 300 Series Specifications

General

Brand	Trane
Model	RTAC 300 Series
Category	Chiller
Language	English