York Screw Chiller YCIV0157PA46

Warning: Ensure the vapor portion of the refrigerant container or cylinder has not been contaminated with other gases that are not R-134a, including air.

Is the appropriate saturation property for the correct refrigerant used?

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 only refrigerant vapor from the top of the drum or cylinder admitted to the system until system pressure is raised above the corresponding saturation pressure at the freezing point of the chilled liquids?

For all other liquids, establish the freeze point temperature and vapor charge to a pressure that is 5°F (2.78°C) higher than that freeze point.

Enter the pressure for water with R-134a at 32°F.

Before charging, establish the starting weight for the refrigerant cylinder.

Has the chiller been vapor charged to the appropriate saturation pressure?

A refrigerant pump may be required to draw vapor from the chiller and discharge it to the vapor connection of the refrigerant cylinder.

Connect a high-capacity vacuum pump with indicator to the charging valves

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

Warning: This procedure requires trained personnel with PPE!

All system valves including manual valves and EEVs are 100% open

All valves to the atmosphere are closed with flare caps in place

Enter the unit's initial evacuation level

Enter the system pressure after charging with dry nitrogen

Soap and water solution prepared

Soap solution test performed on each unit fitting joint and weld seams

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

Conducting the optional trace gas leak test

1. To monitor the system pressure over time, install a high-quality, high-resolution analog pressure gauge on one of the service valves

Use a pressure gauge that has a resolution of 2 psi increments with a dial face at 3 in. in diameter or greater

2. 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

3. Before proceeding, ensure that the unit is at the initial evacuation level of 5 mmHg

To prevent freezing of any moisture that might be in the system, do not go below 5 mmHg

See System evacuation on page 309 for more details

4. With the system evacuated, charge with a vapor only for a 10% trace gas, R-134a based on nameplate, into the chiller until the system pressure reaches 10 psig (69 kPa)