Loosen the compressor holddown bolts to allow free spring travel. Open the compressor suction and discharge service valves. Check that oil is visible in the compressor sight glass. Add oil if necessary.

See Pumpout and Refrigerant Transfer Procedures and Optional Pumpout System Maintenance sections, pages 59 and 65, for details on transfer of refrigerant, oil speci®ca- tions, etc.

High Altitude Locations Ð Recalibration of the pres- sure transducers will be necessary as the chiller was initially calibrated at sea level. Please see the calibration procedure in the Troubleshooting Guide section.

Charge Refrigerant into Chiller

The transfer, addition, or removal of refrigerant in spring isolated chillers may place severe stress on external pip- ing if springs have not been blocked in both up and down directions.

The standard 19XL chiller will have the refrigerant already charged in the vessels. The 19XL may be ordered with a nitrogen holding charge of 15 psig (103 kPa). Evacu- ate the entire chiller, and charge chiller from refrigerant cylinders.

19XL CHILLER EQUALIZATION WITHOUT PUMP- OUT UNIT

When equalizing refrigerant pressure on the 19XL chiller after service work or during the initial chiller start-up, do not use the discharge isolation valve to equalize. The motor cooling isolation valve or charging hose (con- nected between pumpout valves on top of cooler and condenser) is to be used as the equalization valve.

To equalize the pressure differential on a refrigerant isolated 19XL chiller, use the TERMINATE LOCKOUT function of the Control Test in the SERVICE menu. This will help to turn on pumps and advise the proper procedure. The following procedure describes how to equalize refrig- erant pressure on an isolated 19XL chiller without a pump- out unit:

1.Access TERMINATE LOCKOUT function on the Con- trol Test.

2.Turn on the chilled water and condenser water pumps to ensure against freezing.

3.Slowly open the refrigerant cooling isolation valve. The chiller cooler and condenser pressures will grad- ually equalize. This process will take approximately 15 minutes.

4.Once the pressures have equalized, the cooler isolation valve, the condenser isolation valve, and the hot gas by- pass isolation valve may now be opened. Refer to Fig. 27 and 28, valves 11, 12, and 14.

Whenever turning the discharge isolation valve, be sure to reattach the valve locking device. This will prevent the valve from opening or closing during serv- ice work or during chiller operation.

Table 7 Ð Control Test Menu Functions

TESTS TO BE

DEVICES TESTED

PERFORMED

 

1.Automated Tests* Operates the second through seventh tests

2. PSIO Thermistors

Entering chilled water

 

Leaving chilled water

 

Entering condenser water

 

Leaving condenser water

 

Discharge temperature

 

Bearing temperature

 

Motor winding temperature

 

Oil sump temperature

3.Options Thermistors Common chilled water supply

sensor

Common chilled water return sensor Remote reset sensor Temperature sensor Ð Spare 1

Spare 2

Spare 3

Spare 4

Spare 5

Spare 6

Spare 7

Spare 8

Spare 9

4. Transducers

Evaporator pressure

 

Condenser pressure

 

Oil pressure differential

 

Oil pump pressure

5.Guide Vane Actuator Open Close

6. Pumps

All pumps or individual pumps may

 

be activated:

 

Oil pump Ð Con®rm pressure

 

Chilled water pump Ð Con®rm ¯ow

 

Condenser water pump Ð Con®rm

 

¯ow

7.Discrete Outputs All outputs or individual outputs may be energized:

Hot gas bypass relay Oil heater relay Motor cooling relay Tower fan relay Alarm relay

Shunt trip relay

8.Pumpdown/Lockout When using pumpdown/lockout, observe freeze up precautions when removing charge:

Instructs operator as to which valves to close and when

Starts chilled water and condenser water pumps and con®rms ¯ows

Monitors Ð Evaporator pressure Condenser pressure Evaporator temperature during pumpout procedures

Turns pumps off after pumpdown Locks out compressor

9.Terminate Lockout Starts pumps and monitors ¯ows

Instructs operator as to which values to open and when

Monitors Ð Evaporator pressure Condenser pressure Evaporator temperature during charging process

Terminates compressor lockout

10.Refrigerant Type Sets refrigerant type used: HCFC-22 or HFC-134a.

NOTE: Be sure to ATTACH TO LOCAL DEVICE after changing refrigerant type.

See Attach to Network Device Control section, page 37.

*During any of the tests that are not automated, an out-of-range read- ing will have an asterisk (*) next to the reading and a message will be displayed.

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Carrier Charge Refrigerant into Chiller, 19XL Chiller Equalization Without PUMP- OUT Unit, Control Test Menu Functions

19XL specifications

The Carrier 19XL is a highly regarded commercial heating and cooling solution, designed to provide optimum performance and energy efficiency in various applications. This rooftop unit is engineered to meet the diverse needs of businesses, making it an ideal choice for those requiring reliable climate control in their facilities.

One of the standout features of the Carrier 19XL is its advanced cooling and heating capabilities. The unit utilizes a high-efficiency scroll compressor that ensures a quieter operation and improved reliability. The system can operate across a wide range of temperatures, making it versatile for various climates. Additionally, it offers both cooling and heating options, allowing for year-round comfort.

Energy efficiency is a focal point of the 19XL design. With an impressive Seasonal Energy Efficiency Ratio (SEER) and Heating Seasonal Performance Factor (HSPF), this unit not only helps reduce energy costs but also supports environmental sustainability initiatives. The unit is equipped with environmentally friendly refrigerants, further contributing to lower greenhouse gas emissions.

The Carrier 19XL features a user-friendly control system, allowing for easy monitoring and management of the unit's performance. This control system is designed to maximize energy savings, offering features such as demand control ventilation and integrated economizers that facilitate the use of outdoor air for cooling, reducing reliance on mechanical systems when conditions allow.

Construction-wise, the Carrier 19XL is built to withstand tough environmental conditions. Its robust cabinet is made from galvanized steel, providing durability and protection against the elements. The design also includes insulation to minimize noise levels, creating a more comfortable indoor environment.

Maintenance is a key consideration in the design of the 19XL. The unit features accessible service ports and a simplified access panel, allowing technicians to perform routine maintenance with ease. This proactive design helps ensure the longevity of the system and minimizes downtime, keeping operations running smoothly.

In summary, the Carrier 19XL is an exceptional choice for commercial heating and cooling needs. With its energy-efficient features, advanced technology, and durable construction, it stands out as a reliable solution for businesses looking for sustainable climate control options.