McQuay SB00B, Installation Manual

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2. Charging procedures – Three phase compressors
The fundamental procedure is the same as for single phase models but the compressor can run in the wrong direction on
starting. If this happens reverse any two phases and start again. Short term reverse rotation will not damage the compressor.
All Specter compressors have internal discharge temperature protectors which are very effective in preventing dangerously
high discharge temperatures during charging. The protection module will trip and lock the compressors out for 30 minutes.
It is not normally necessary to wait 30 minutes for the module to reset. When the compressor has cooled down the module
can be reset by breaking the power supply to the control circuit. Very often the serviceman does not understand why the
module tripped and uses a jumper wire to bypass it. He continues to charge the system and removes the jumper when
charging is complete. The compressor may or may not run with the protector back in the circuit but it is certain that the
compressor has been damaged and premature failure is inevitable.
• 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.
!
Caution
STANDARD OPERATING CONDITIONS
Heating Cooling
Temperature
Ts °C Th °C
Minimum indoor
16 11
temperature
Maximum indoor
32 23
temperature
Minimum outdoor
16 11
temperature
Maximum outdoor
46 24
temperature
Temperature
Ts °C Th °C
Minimum indoor
16 -
temperature
Maximum indoor
30 -
temperature
Minimum outdoor
-5 -6
temperature
Maximum outdoor
24 18
temperature
Ts: Dry bulb temperature.
Th: Wet bulb temperature.
!
Warning
• Disconnect from the main power supply before servicing the air conditioner unit.
• DO NOT pull out the power cord when the power is ON. This may cause serious electrical shocks which may
result in fire hazards.
AUTO RANDOM RE-START FUNCTION
If there is a power cut when the unit is operating, it will automatically resume the same operating mode when the power is
restored. (Applicable only to units with this feature)
!
Caution
Before turning off the power supply, set the remote controller's ON/OFF switch to the “OFF” position to prevent the
nuisance tripping of the unit.
If this is not done, the unit's fans will start turning automatically when power resumes, posing a hazard to service
personnel or the user.