Trane RTAC 140-500 ton units (60 Hz) User Manual
RTAC-SVX01F-EN
145
Unit Start-Up Procedures
Once the system has been operating for approximately 30 minutes and has become
stabilized, complete the remaining start-up procedures, as follows:
stabilized, complete the remaining start-up procedures, as follows:
1.
Check the evaporator refrigerant pressure and the condenser refrigerant pressure
under Refrigerant Report on the CH530 TechView. The pressures are referenced
to sea level (14.6960 psia).
under Refrigerant Report on the CH530 TechView. The pressures are referenced
to sea level (14.6960 psia).
2.
Check the EXV sight glasses after sufficient time has elapsed to stabilize the
chiller. The refrigerant flow past the sight glasses should be clear. Bubbles in the
refrigerant indicate either low refrigerant charge or excessive pressure drop in the
liquid line or a stuck open expansion valve. A restriction in the line can sometimes
be identified by a noticeable temperature differential between the two sides of
the restriction. Frost will often form on the line at this point. Proper refrigerant
charges are shown in the General Information Section.
chiller. The refrigerant flow past the sight glasses should be clear. Bubbles in the
refrigerant indicate either low refrigerant charge or excessive pressure drop in the
liquid line or a stuck open expansion valve. A restriction in the line can sometimes
be identified by a noticeable temperature differential between the two sides of
the restriction. Frost will often form on the line at this point. Proper refrigerant
charges are shown in the General Information Section.
NOTE:
Important! A clear sight glass alone does not mean that the system is
properly charged. Also check system subcooling, liquid level control and unit
operating pressures.
operating pressures.
3.
Measure the system subcooling.
4.
A shortage of refrigerant is indicated if operating pressures are low and subcool-
ing is also low. If the operating pressures, sight glass, superheat and subcooling
readings indicate a refrigerant shortage, gas-charge refrigerant into each circuit,
as required. With the unit running, add refrigerant vapor by connecting the charg-
ing line to the suction service valve and charging through the backseat port until
operating conditions become normal.
ing is also low. If the operating pressures, sight glass, superheat and subcooling
readings indicate a refrigerant shortage, gas-charge refrigerant into each circuit,
as required. With the unit running, add refrigerant vapor by connecting the charg-
ing line to the suction service valve and charging through the backseat port until
operating conditions become normal.
CAUTION
Refrigerant!
Refrigerant!
If both suction and discharge pressures are low but sub-cooling is
normal, a problem other than refrigerant shortage exists. Do not add
refrigerant, as this may result in overcharging the circuit.
normal, a problem other than refrigerant shortage exists. Do not add
refrigerant, as this may result in overcharging the circuit.
Use only refrigerants specified on the unit nameplate (HFC 134a) and
Trane OIL00048. Failure to do so may cause compressor damage and
improper unit operation.
Trane OIL00048. Failure to do so may cause compressor damage and
improper unit operation.
Seasonal Unit Start-Up Procedure
1.
Close all valves and re-install the drain plugs in the evaporator.
2.
Service the auxiliary equipment according to the start-up/maintenance instruc-
tions provided by the respective equipment manufacturers.
tions provided by the respective equipment manufacturers.
3.
Close the vents in the evaporator chilled water circuits.
4.
Open all the valves in the evaporator chilled water circuits.
5.
Open all refrigerant valves to verify they are in the open condition.
6.
If the evaporator was previously drained, vent and fill the evaporator and chilled
water circuit. When all air is removed from the system (including each pass),
install the vent plugs in the evaporator water boxes.
water circuit. When all air is removed from the system (including each pass),
install the vent plugs in the evaporator water boxes.
7.
Check the adjustment and operation of each safety and operating control.
8.
Close all disconnect switches.
9.
Refer to the sequence for daily unit startup for the remainder of the seasonal star-
tup.
tup.