McQuay MDB075B, Manual

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Installation (Indoor)
Preliminary Site Survey
a) Electrical supply and installation is to confirm to local authority’s (e.g. National Electricity Board) codes
and regulations.
b) Voltage supply fluctuation must not /- 10% of rated voltage. Electricity supply line must be
independent of welding transformers which can cause supply fluctuation.
c) Ensure that the location is convenient for wiring and piping.
Mounting
a) For ceiling mounted models, locate a position where piping and ducting work can be kept to a minimum.
Ensure that overhead supports are strong enough to hold the unit’s weight. Position hanger rods and
check for alignment with the unit. Check that hangers are secure and that the base of fan-coil unit is level
in two horizontal directions.
Pipings
Do not use contaminated or damaged copper tubings. If pipings, evaporator or condenser are exposed or
had been opened for 15 seconds or more, vacuum and purge with field supplied refrigerant. Generally, do
not remove plastic/rubber plugs/caps from fittings, tubings and coils until ready to connect suction or liquid
line into fittings.
Operational Check
After all electrical wiring is completed and the system is charged with refrigerant, make sure unit is operating
properly. Check that:
a) Condenser fans are running, with warm air blowing off the condenser coil.
b) Evaporator blowers are running and discharging cool air.
c) Suction line inside condensing unit feels cool.
d) Liquid line inside condensing unit feels warm.
Electrical Connection
As wiring regulations differ from country to country, please refer to your LOCAL ELECTRICAL CODES for
field wiring regulations and ensure that these are complied with. Besides, observe the following general
precautions:
a) Ensure that the rated voltage of the unit corresponds to that of the name plate before commencing wiring
work.
b) Provide a power outlet to be used exclusively for each unit. A power supply disconnect and a circuit
breaker for over-current protection should be provided in the exclusive line.
c) The unit must be GROUNDED to prevent possible hazard due to insulation failure.
d) All wiring must be firmly connected.
e) Electrical wiring must not touch the refrigerant piping, compressor and any moving parts of the fan
motors.