Precautions On Refrigerant Piping; Guidelines For Brazing; Guidelines For Flare Connection - Rotex Rrrq011Aav1 Installationsanleitung

6. P
RECAUTIONS ON REFRIGERANT PIPING
Do not allow anything other than the designated refrigerant to
get mixed into the freezing cycle, such as air, etc. If any
refrigerant gas leaks while working on the unit, ventilate the
room thoroughly right away.
Use R410A only when adding refrigerant
Installation tools:
Make sure to use installation tools (gauge manifold charge hose,
etc.) that are exclusively used for R410A installations to withstand
the pressure and to prevent foreign materials (e.g. mineral oils
and moisture) from mixing into the system.
Vacuum pump:
Use a 2-stage vacuum pump with a non-return valve
Make sure the pump oil does not flow oppositely into the system
while the pump is not working.
Use a vacuum pump which can evacuate to –100.7 kPa (5 Torr,
–755 mm Hg).
In order to prevent dirt, liquid or dust from entering the piping,
cure the piping with a pinch or taping.
Installation period
More than a month
Less than a month
Regardless of the period
Great caution is needed when passing copper tubes through
walls.
For handling of stop valves, refer to "6.3. Guidelines for handling
stop valve" on page 8.
Only use the flare nuts included with the unit. Using different
flare nuts may cause the refrigerant to leak.
Ensure that the field piping and connections are not subjected to
stress.
Use appropriate fire resistant piping insulation according to
national regulations.
RRRQ011~016AAV1+Y1
Outdoor unit for air to water heat pump
4PW55782-1

6.1. Guidelines for brazing

Protection method
Pinch the pipe
Pinch or tape the pipe
6.2. Guidelines for flare connection
Make sure to blow through with nitrogen when brazing.
Blowing through with nitrogen prevents the creation of large
quantities of oxidized film on the inside of the piping. An oxidized
film adversely affects valves and compressors in the
refrigerating system and prevents proper operation.
The nitrogen pressure should be set to 0.02 MPa (i.e., just
enough so it can be felt on the skin) with a pressure-reducing
valve.
1 2
6
1 Refrigerant piping
2 Part to be brazed
3 Taping
4 Hands valve
5 Pressure-reducing valve
6 Nitrogen
Do not use anti-oxidants when brazing the pipe joints.
Residue can clog pipes and break equipment.
Do not use flux when brazing copper-to-copper refrigerant
piping. Use phosphor copper brazing filler alloy (BCuP) which
does not require flux.
Flux has an extremely harmful influence on refrigerant piping
systems. For instance, if chlorine based flux is used, it will cause
pipe corrosion or, in particular, if the flux contains fluorine, it will
deteriorate the refrigerant oil.
Flares should not be re-used. New ones should be made in
order to prevent leaks.
Use a pipe cutter and flare tool suitable for the refrigerant used.
Only use the annealed flare nuts included with the unit. Using
different flare nuts may cause the refrigerant to leak.
Please refer to the table for flaring dimensions and tightening
torques (too much tightening will result in splitting the flare).
Piping size Tightening Flare dimensions A
(mm) torque (N•m)
Ø9.5 33~39
Ø15.9 63~75
When connecting the flare nut, coat the flare inner surface with
ether oil or ester oil and initially tighten 3 or 4 turns by hand
before tightening firmly.
3 4 5
6
Flare shape
(mm) (mm)
90 ±2
12.8~13.2
A
R=0.4~0.8
19.4~19.7
Installation manual
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