McQuay 5ACV 30 CR, Installation Manual

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SPECIAL PRECAUTIONS WHEN DEALING WITH R410A UNIT
• R410A is a near azeotrope refrigerant blend of hydro fluorocarbon (HFC) which is environmental friendly. It has Zero
Ozone Depletion Potential (ODP=0) and this conforms to Montreal Protocol regulations. It has no flame propagation and
a low toxic refrigerant (rated as A1 by ARI). R410A is a mixture of R32 (50%) and R125 (50%).
• POE oil is used as lubricant for R410A 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 R410A system too long to moist air.
Residual POE oil in the piping and components can absorb moisture from the air.
• Refrigerant R410A 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 additional charge of compressor oil only is permitted.
• No refrigerant other than R410A is permitted.
• Tools designed specifically for R410A only.
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
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CAUTION
• R410A must be charged as liquid. Usually R410A 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 R410A 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 R410A 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.
REFRIGERANT CIRCUIT
• All chiller units are pre-charged with R410A refrigerant.