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Pre-commissioning and Maintenance
Due to our policy of continuous product innovation, some specifications may change without notification.
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PRE-COMMISSIONING
Open all isolation valves that may have been installed in the piping system. Water source unit service valves must remain closed.
Prepare the Refrigerant Piping System
Note:
Perform a Pressure (Leak) Test
Use medical grade dry nitrogen, and pressure test the refrigerant piping system using a multi step process that will assist in locating leaks (if
any).
Pressure test the segment of piping between the water source unit and the main pipes. If the test is successful the pipes do not have
leaks.
• 150 psi for a period of 5 minutes
• 300 psi for a period of 15 minutes
• 550 psi for a period of 24 hours
1. Release the Pressure Test dry nitrogen charge from all refrigerant pipes.
2. Verify ALL field installed isolation ball valves are OPEN (including those that are capped for future use).
3. Remove and discard the Schrader valve cores at the water source unit charging ports. (This is a preventive step that ensures that valves
used after charging the system have not been subjected to the high pressure value used during the Pressure Test.)
4. Attach a 5/16” core removal tool equipped with ball valve and a fresh core to each charging port on the water source unit.
5. Check the vacuum pump(s) you intend to use and verify the oil in the sump is fresh and not contaminated..
6. Attach the vacuum pump(s) to each charging port simultaneously using high quality refrigerant vacuum hoses.
7. Perform a triple evacuation.
8. Achieve a micron gauge reading of less than 500 microns.
9. At 500 microns, valve off the charging port by closing the core removal tool ball valves.
10. Remove the vacuum hoses and pumps.
Evacuate the Refrigerant Piping System
Note:
The water source unit may be put in “vacuum mode”. Generally, using the vacuum mode feature does assist with the vacuum process and
is not necessary if a vacuum pump is connected to all charging ports at the water source unit simultaneously as suggested herein. See the
Technical Service Manual for this product for more information.
Do not open the water source unit service valves and release the factory refrigerant charge until the Commissioning Agent authorizes to do so.
11. Leave the refrigerant piping system in a vacuum until the Commissioning Agent arrives and is satisfied with the micron gauge reading.
Note:
• There is no danger in doing this as all piping and equipment are dry and have never had oil in them.
•
The system must be left in a vacuum until the Commissioning Agent arrives and verifies the quality of the evacuation process. If the evacu
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ation procedure was not conducted properly, the system will likely malfunction and operate erratically. Significant costs may be incurred
including but not limited to refrigerant reclaim, recycle, and replacement.
Note: