York Screw Chiller YCIV0207VA46

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)

Refrigerant charge removed and all known leaks repaired?

System charged with a small amount of refrigerant mixed with dry nitrogen?

Electronic leak detector used to detect any small leaks?

Rated pressure of the unit refrigerant pressure relief valves not exceeded?

Conducting the gas pressure hold test

High-quality, high-resolution analog pressure gauge installed on one of the service valves?

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

All valves to the atmosphere are closed with flare caps in place, if applicable?

Warning: This procedure should only be performed by a qualified technician.

Has the system been carefully pressure tested and evacuated at the factory?

Enter the leak rate for the R-134a system at DWP (acceptable limit is 0.1 oz/year)

Are all joints tight and leak-free?

If any leaks are indicated, they must be repaired immediately.

Have all face seal nuts and flange bolts been correctly torqued?

For any major repair, the refrigerant charge must be removed and the system leak checked using reliable methods like a pressure test.

This procedure must be performed by an industry certified technician

Maintain a record of this procedure for warranty purposes

Superheat on the economizer feed to the compressor

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.