Installation manual
7
ERSQ+ERRQ011~Y1
Outdoor unit for air to water heat pump
4PW49635-1A
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.
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.
6.1.
Guidelines for brazing
■
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.
■
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.
6.2.
Guidelines for flare connection
■
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).
■
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.
■
When loosening a flare nut, always use two wrenches together.
When connecting the piping, always use a spanner and torque
wrench together to tighten the flare nut to prevent flare nut
cracking and leaks.
Installation period
Protection method
More than a month
Pinch the pipe
Less than a month
Pinch or tape the pipe
Regardless of the period
1
Refrigerant piping
2
Part to be brazed
3
Taping
4
Hands valve
5
Pressure-reducing valve
6
Nitrogen
Piping size
(mm)
Tightening
torque (N•m)
Flare dimensions A
(mm)
Flare shape
(mm)
Ø9.5
33~39
12.8~13.2
Ø15.9
63~75
19.4~19.7
1
2
3
4
5
6
6
R=0.4~0.8
45
±
2
90
±
2
A
4
2
3
1
1
Piping union
2
Spanner
3
Flare nut
4
Torque wrench
Содержание ERSQ011AAV1
Страница 22: ...4PW49635 1A Copyright Daikin...
