English
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CAUTION
• The connecting piping must be insulated all the way to the piping connection parts within the unit. If the piping is exposed, it may
cause condensation and scald when touched.
• Flux should not be used when brazing the connecting parts of the refrigerant piping. Please use phosphor copper brazing filler
metal (BCuP-2) which requires no flux.
(If chlorine-containing flux is used, piping will be corroded. If fluorine-containing flux is used, the refrigerant oil will deteriorate and
even further affect the refrigerant piping system.)
• Before brazing the refrigerant piping purchased locally, fill in nitrogen into the piping in order to exhaust the air from there. If no
nitrogen is filled in at brazing, a large quantity of oxide films will occur within the piping and cause failure of the machine.
• Before brazing the refrigerant piping, firstly carry out nitrogen substitution or fill the refrigerant piping with nitrogen gas, and finally
connect the indoor unit with a flare opening.
• When filling nitrogen into the piping during brazing, pressure should be set to below 0.02 MPa (0.2 kg/cm
2
) with a pressure-reduc-
ing valve.
DRAIN PIPING WORK
WARNING
The drain pipe must be installed as shown in the diagram below to avoid damage caused by leaks and
condensation.
• Assemble the unit as shown in Fig.14.
• The drain pipe outlet can be installed on either the left or right side. The drain plug can be removed and placed on either the left or
right side as well.
• For best results, try to keep the piping as short as possible. Slant the piping at an angle to improve flow. (Refer to Fig.14)
• Ensure heat insulation of the drain pipe.
• It is necessary to install a drain trap in the drain outlet to relieve negative pressure that exists within the unit compared to the out-
side atmospheric pressure when the unit is operating. If a drain trap is not provided, splashes or odor may be produced.
• Keep the drainage pipes as straight as possible for easy cleaning and to prevent the accumulation of dirt and debris.
• After closing the drain pipe on the opposite side of the unit, completely wrap the drain pipes with insulation. (Refer to Fig.14)
• Drain piping connections
Do not connect the drain piping directly to sewage pipes that smell of ammonia. The ammonia in the sewage might enter the indoor
unit through the drain pipes and corrode the heat exchanger.
• Follow the illustrations below if concentrated drainage pipelines are installed.
(Please choose drainage pipelines with a diameter suitable for the operational volume of the equipment for the connection.)
• Pour water in the drain pan to test for smooth drainage.
• Open the service cover, add approximately 1 liter of water gradually and check drainage flow.
• In humid environments, use an extra drain pan (field supply) to cover the entire area of the indoor unit.
Part to be
brazed
Nitrogen
Refrigerant piping
Taping
Hands valve
Pressure-reducing
valve
Nitrogen
01_EN_3PR05311-2.fm Page 11 Tuesday, June 2, 2009 4:39 PM
