Water Piping System Setup; Refrigerant Circuit; Special Precautions When Dealing With R407C Unit - McQuay C Serie Installationsanleitung

• Fill up the water circuit after connecting all the pipes and equipment. Perform leak checks for all connections and joints.
Do not start the unit when the system is leaking.
• To optimize the capacity of the system, ensure that the system is free of air bubbles. The air trapped in the system would
make the system unbalanced.
• Ensure that the water tank is not full. This is to ensure optimal performance of the mini chiller. If the pressure is too high,
release the pressure from the auto pressure relief valve on the tank.
• All mini chiller units are pre-charged with R22 or R407C refrigerant.

SPECIAL PRECAUTIONS WHEN DEALING WITH R407C UNIT

• R407C is a zeotropic refrigerant mixture which has zero ozone depletion potential and thus conformed to the Montreal
Protocol regulation. It requires Polyester oil (POE) oil for its compressor lubricant. Its refrigerant capacity and perfor-
mance are about the same as the refrigerant R22.
• POE oil is used as lubricant for R407C compressor, which is different from the mineral oil used for R22 compressor.
During installation or servicing, extra precaution must be taken not to expose the R407C system too long to moist air.
Residual POE oil in the piping and components can absorb moisture from the air.
• Refrigerant R407C is more easily affected by dust of moisture compared with R22, make sure to temporarily cover the
ends of the tubing prior to installation.
• No additonal charge of compressor oil is permitted.
• No other refrigerant other than R407C.
• Tools specifically for R407C only (must not be used for R22 or other refrigerant)
i) Manifold gauge and charging hose
ii) Gas leak detector
iii) Refrigerant cylinder/charging cylinder
iv) Vacuum pump c/w adaptor
v) Flare tools
vi) Refrigerant recovery machine
• R407C must be charged as liquid. Usually R407C cylinder is equipped with a dip-pipe for liquid withdrawal.
If there is no dip-pipe, the cylinder should be inverted so as to withdraw liquid R407C from the valve.
• Do not top-up when servicing leak, as this will reduce the unit performance. Vacuum the unit thoroughly and then
charge the unit with fresh R407C according to the amount recommended in the specification.
• Do not touch the compressor or refrigerant piping when the chiller is running. If necessary wear protective gloves.

WATER PIPING SYSTEM SETUP

REFRIGERANT CIRCUIT

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