Daikin VRV III REYQ8PY1, Service Manual

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Troubleshooting (OP: Unified ON/OFF Controller) Si37-701
358 Troubleshooting
[Check 13] Vacuuming and dehydration procedure
Conduct vacuuming and dehydration in the piping system following the procedure for <Normal
vacuuming and dehydration> described below.
Furthermore, if moisture may get mixed in the piping system, follow the procedure for <Special
vacuuming and dehydration> described below.
<Normal vacuuming and dehydration>
Vacuuming and dehydration
• Use a vacuum pump that enables vacuuming up to 100.7kPa (5 torr, -755 mmHg).
• Connect manifold gauges to the service ports of liquid pipe and gas pipe and run the
vacuum pump for a period of two or more hours to conduct evacuation to -100.7kPa or
less.
• If the degree of vacuum does not reach -100.7kPa or less even though evacuation is
conducted for a period of two hours, moisture will have entered the system or refrigerant
leakage will have been caused. In this case, conduct evacuation for a period of another
one hour.
• If the degree of vacuum does not reach -100.7kPa or less even though evacuation is
conducted for a period of three hours, conduct leak tests.
Leaving in vacuum state
• Leave the compressor at the degree of vacuum of -100.7kPa or less for a period of one
hour or more, and then check to be sure that the vacuum gauge reading does not rise. (If
the reading rises, moisture may have remained in the system or refrigerant leakage may
have been caused.)
Refrigerant charge
• Purge air from the manifold gauge connection hoses, and then charge a necessary
quantity of refrigerant.
<Special vacuuming and dehydration> - In case moisture may get mixed in the piping*
Vacuuming and dehydration
• Follow the same procedure as that for 1) Normal vacuuming and dehydration described
above.
Vacuum break
• Pressurize with nitrogen gas up to 0.05MPa.
Vacuuming and dehydration
• Conduct vacuuming and dehydration for a period of one hour or more. If the degree of
vacuum does not reach -100.7kPa or less even though evacuation is conducted for a
period of two hours or more, repeat vacuum break - vacuuming and dehydration.
Leaving in vacuum state
• Leave the compressor at the degree of vacuum of -100.7kPa or less for a period of one
hour or more, and then check to be sure that the vacuum gauge reading does not rise.
Refrigerant charge
• Purge air from the manifold gauge connection hoses, and then charge a necessary
quantity of refrigerant.
∗
In case of construction during rainy reason, if dew condensation occurs in the piping due
to extended construction period, or rainwater or else may enter the piping during
construction work: