York Screw Chiller YCIV0227VA46

Connect a high-capacity vacuum pump with indicator to the charging valves as shown in Figure 147 on page 306 and Figure 148 on page 306

Ensure all the system valves including manual valves and EEVs are 100% open

Ensure that all valves to the atmosphere are closed with flare caps in place, if applicable

Operate the vacuum pump until a pressure of 5,000 μm is reached

To start the 8-hour vacuum hold test, close the system charging valve connection to the vacuum pump

Hold the vacuum obtained in Step 4 in the system for 8 hours

Check for pressure change with the chiller at the same temperature

The following maintenance checks should be carried out on a daily basis by the operator/customer

The units are not generally user serviceable

No attempt should be made to rectify faults or problems found during daily checks unless competent and equipped to do so

If in any doubt, contact your local Johnson Controls Service Agent

Unit status: Press the STATUS key on the keypad and ensure no fault messages are displayed

Operating conditions: Read the operating pressures and temperatures at the control panel using the display keys

Check that these are within the operating limitations given in the manual

Compressor oil level: Check the compressor oil level after the compressor has been operating on FULL LOAD for approximately half an hour

Check oil level in the oil separator sight glass

Check liquid line sight glass / moisture indicator

Record system operating temperatures

Record system operating pressures

Check condenser coils for dirt/debris

Clean condenser coils if necessary

Sign off on the weekly chiller check

Warning: Only trained personnel should perform this procedure.

Is the vapor portion of the refrigerant container or cylinder free from contamination?

Select the appropriate saturation property for the refrigerant

Refer to Table 55 on page 314 for R-134a to determine if the saturation pressure and ambient temperature of the refrigerant in the container coincide.

Is the system pressure raised above the corresponding saturation pressure at the freezing point of the chilled liquids?

Enter the freeze point temperature

Enter the vapor charge pressure

Enter the starting weight for the refrigerant cylinder

Is the chiller vapor charged to the appropriate saturation pressure?

This procedure must be performed at the specified time by an industry certified technician who has been trained and qualified to work on this type of equipment.

A record of this procedure being successfully carried out should be maintained on file by the equipment owner should proof of adequate maintenance be required at a later date for warranty purposes.

Sample compressor oil, check for acid, and replace if necessary.

Disconnect power source and lock out and check tightness of power wiring connections.

Check glycol concentration on low temperature or other applications where freezing may be a problem.