Daikin LREQ15B7Y1R, Installation Manual

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20B7Y1R
Air cooled refrigeration condensing unit
4P360438-1B – 2014.01
Installation manual
8
6-2 Protection against contamination when
installing pipes
Protect the piping to prevent moisture, dirt, dust, etc. from entering the
piping.
Note
Exercise special caution to prevent dirt or dust when passing piping
through holes in walls and when passing pipe edges to the exterior.
6-3 Pipe connection
• Be sure to perform nitrogen permutation or nitrogen blow when brazing.
Brazing without performing nitrogen permutation or nitrogen blow
into the piping will create large quantities of oxidized film on the
inside of the pipes, adversely affecting valves and compressors in
the refrigerating system and preventing normal operation.
• The pressure regulator for the nitrogen released when doing the
brazing should be set to 0.02 MPa (about 0.2 kg/cm
2
:Enough to
feel a slight breeze on your cheek).
Note
Do not use anti-oxidants when brazing the pipe joints.
Residue can clog pipes and break equipment.
6-4 Connecting the refrigerant piping
CAUTION
• In addition to gas and liquid shutoff valves, this unit has a
maintenance shutoff valve (see diagram below).
• Do not operate the maintenance shutoff valve*.
(The factory setting for the maintenance shutoff valve is “open.”
During operation, always leave this valve in the open position.
Operating the unit with the valve in the closed position may cause
the compressor to fail.)
Piping between
branching areas (B, b,
C, c) Select the piping from the following table in accordance with the total capacity of indoor units connected
downstream
Total capacity of indoor units after branching
Liquid pipe size
less than 4.0 kW Ø6.4 x 0.8 (O type)
4.0 kW over and less than 14.0 kW Ø9.5 x 0.8 (O type)
14.0 kW over and less than 30.0 kW Ø12.7 x 0.8 (O type)
30.0 kW over and less than 50.0 kW Ø15.9 x 1.0 (O type)
50.0 kW or over Ø19.1 x 1.0 (O type)
Total capacity of indoor units after branching
Gas pipe size
Medium temperature
(–20°C or more)
Low temperature
(–20°C or less)
less than 1.0 kW — Ø9.5 x 0.8 (O type)
1.0 kW over and less than 6.0 kW less than 1.5 kW Ø12.7 x 0.8 (O type)
6.0 kW over and less than 9.9 kW 1.5 kW over and less than 2.5 kW Ø15.9 x 1.0 (O type)
9.9 kW over and less than 14.5 kW 2.5 kW over and less than 3.8 kW Ø19.1 x 1.0 (O type)
14.5 kW over and less than 25.0 kW 3.8 kW over and less than 5.9 kW Ø22.2 x 1.0
(1/2 H or H type)
25.0 kW over and less than 31.0 kW 5.9 kW over and less than 9.8 kW Ø28.6 x 1.0
(1/2 H or H type)
31.0 kW or over and less than 40.0 kW 9.8 kW over and less than 19.0 kW Ø34.9 x 1.2
(1/2 H or H type)
40.0 kW or over 19.0 kW or over Ø41.3 x 1.45
(1/2 H or H type)
No size after branching can exceed the size of any upstream piping.
Piping between
branching areas and
each unit Adjust the size of the piping so that it will coincide with the size of piping connecting to the indoor unit
Place Installation period Protection method
Outdoor
More than a month Pinch the pipe
Less than a month
Pinch or tape the pipe
Indoor Regardless of the period
Refrigerant pipe
Regulator
Handy valve
Taping
Nitrogen
Nitrogen
Location to
be brazed
Liquid side shutoff valve
(provided with service port)
Gas side shutoff valve
(provided with service port)
* Maintenance shutoff valve
(Do not operate)
(Do not operate)
* Maintenance shutoff valve