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Installation manual
11
R REMQ10~16P8 + REMHQ12P8Y1B
VRVIII System air conditioner
4PW48463-1A
7.
L
EAK
TEST
AND
VACUUM
DRYING
The units were checked for leaks by the manufacturer.
After connecting the field piping, perform the following inspections.
1
Preparations
Referring to
figure 23
, connect a nitrogen tank, a refrigerant tank
and a vacuum pump to the outdoor unit and perform the
airtightness test and the vacuum drying.
The refrigerant tank and the charge hose connected to the
refrigerant charge port or valve A are needed to perform
refrigerant charging.
2
Airtightness test and vacuum drying
■
Airtightness test:
Pressurize the liquid pipe, the suction gas pipe, the high
pressure/low pressure gas pipe and the equalizer pipe from the
service ports of each stop valve to 4.0 MPa (40 bar) (do not
pressurize more than 4.0 MPa (40 bar)). If the pressure does not
drop within 24 hours, the system passes the test. If the pressure
drops, check where the nitrogen leaks from.
Note 1
When the equiv
alent pipe length betw
een outdoor and indoor units is 90 m or more
, the siz
e of the main
liquid pipe m
ust be increased.
Ne
v
er increase suction gas pipe and HP/LP gas pipe siz
es
.
Depending on the length of the piping, the capacity ma
y drop
, b
ut e
v
en in such a case it is possib
le to
increase the siz
e of the main liquid pipe
.
Note 2
Allo
w
a
b
le length after the first refr
iger
ant br
anch kit to indoor units is 40 m or less
, ho
w
e
v
er it can be e
xtended up to 90 m i
f all the f
ollo
wing conditions are fulfilled.
Required conditions
Example dra
wings
It is necessar
y to increase the pipe siz
e of the liquid and suction gas pipe if the pipe length betw
een the
first and the final br
anch kit is o
v
er 40 m (reducers m
ust be procured on site).
Increasing the HP/LP gas
pipe siz
e is not allo
w
ed.
■
If the increased liquid pipe siz
e is larger than the pipe siz
e of the main liquid pipe
, then the pipe siz
e of
the main liquid pipe needs to be increased as w
ell.
■
If the increased suction gas pipe siz
e is larger than the pipe siz
e of the main suction gas pipe
, then the
allo
w
a
b
le length after the first refr
iger
ant br
anch kit ma
y not be increased to 90 m.
Siz
e-up of the main suction gas pipe ma
y aff
ect a good oil retur
n to the outdoor unit due to influence of
the HP/LP gas pipe
.
indoor unit
8
:
b+c+d+e+f+g+p
≤
90 m
increase the pipe siz
e
of b
, c
, d, e
, f
, g
Increase the pipe siz
e as f
ollo
ws
F
or calculation of total e
xtension length, the actual length of abo
v
e
pipes m
ust be doub
led (e
xcept length of
main pipes and of pipes which do not ha
v
e
an increased pipe siz
e).
a+b*2+c*2+d*2+e*2+f*2+g*2
+h+i+j+k+l+m+n+p
≤
1000 m
Indoor unit to the nearest br
anch kit
≤
40 m
h, i, j.......
p
≤
40 m
The diff
erence betw
een the distance of the outdoor unit to the f
a
rthest indoor unit and the distance of the
outdoor unit to the nearest indoor unit
≤
40 m
The most remote indoor unit
8
The nearest indoor unit
1
(a+b+c+d+e+f+g+p)–(a+h)
≤
40 m
8+10
12~16
9.5
➞
12.7
12.7
➞
15.9
18~24
26~48
15.9
➞
19.1
19.1
➞
22.2
REY(H)Q
Ø
REY(H)Q
Ø
1
6
2
5
4
3
1
Outdoor unit
4
First refr
iger
ant
br
anch kit
2
Main pipes
3
Increase only liquid
pipe siz
e
5
BS unit
6
Indoor unit
Gas side
Liquid side
REYQ18~22
Ø28.6
➞
Ø31.8
(a)
(a)
If not a
v
ailab
le
, increase is not allo
w
e
d
Ø9.5
➞
Ø12.7
REYQ24
Ø34.9
—
Ø
12.7
➞
Ø15.9
REYQ26~34
Ø34.9
➞
Ø38.1
(a)
Ø15.9
➞
Ø19.1
REYQ36~48
Ø41.3
—
Ø
19.1
➞
Ø22.2
20+22
Ø28.6
➞
Ø31.8
(a)
REYHQ24
Ø34.9
—
— Increase is not allo
w
e
d
ab
c
d
e
f
g
H1
p
AB
C
D
E
F
G
12
3
4
5
6
7
8
H2
hi
j
k
l
m
n
1
2
3
1
Outdoor unit
2
Refnet joints (a~g)
3
Indoor units (1~8)
1
Gauge manifold
2
Nitrogen
3
Measuring instrument
4
Refrigerant R410A tank (siphon system)
5
Vacuum pump
6
Charge hose
7
Equalizer pipe stop valve
8
High pressure/low pressure pipe stop valve
9
Suction gas line stop valve
10
Liquid line stop valve
11
Refrigerant charge port
12
Valve A
13
Valve B
14
Valve C
15
To BS unit or indoor unit
16
Stop valve
17
Service port
18
Field piping
19
Gas flow
NOTE
Make sure to perform airtightness test
and vacuum drying using the service
ports of the stop valves of the
equalizer pipe, HP/LP gas pipe,
suction gas pipe and liquid pipe. (For
the service port location, refer to the
"Caution" label attached on the front
panel of the outdoor unit.)
■
See
"11.3. Stop valve operation procedure" on
page 18
for details on handling the stop valve.
■
To prevent entry of any contamination and to
prevent insufficient pressure resistance, always
use the special tools dedicated for working with
R410A refrigerant.
NOTE
Make sure to use nitrogen gas.
Summary of Contents for VRV III
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