![background image](http://html1.mh-extra.com/html/carrier/38qus012/38qus012_installation-manual_2560794014.webp)
4. REFRIGERANT PIPING WORK
7
GB-13
After the piping work is finished, make sure to check the connection part of each refrigerant pipe and confirm
that there is no gas leak by applying soapy water to them or by using a leak detector specific for HFC refrigerants.
Refer below picture for illustration.
A: Low pressure stop valve B: High pressure stop valve
C& D: Indoor unit flare nuts
Check-point of indoor unit
Check-point of outdoor unit
A
B
C
D
4.4 AIR EVACUATION
Connect the charge hose from the manifold gauge to the service port of the gas side packed valve.
Connect the charge hose to the port of the vacuum pump.
Fully open the handle Lo of manifold gauge.
Operate the vacuum pump to evacuate air from the system until 76cmHg.
Close the handle Lo of manifold gauge.
Fully open the valve stem of the packed valves.
Remove the charging hose from the service port.
Securely tighten caps of packed valve.
-76 cmHg
Handle Lo
Handle Hi
Charge hose
Charge hose
Vacuum pump
Packed valve
Manifold valve
Compound gauge
Pressure meter
4.5 LEAKAGE TEST
4.3 REFRIGERANT PIPE
Gas Side
Liquid Side
Allowable
pipe length (m)
Max. Height
difference (m)
Charge less
length (m)
Additional charge
per meter (R410A/R32)
NOTE: 1) Please use tools for R410A/R32 system respectively;
2) When the pipe length is over 5m, the additional refrigerant should be added according to the
piping length.
Φ
6.35mm
Φ
5
m
m
2
5
.
9
m
/
g
2
1
/
5
1
0
1
5
2
Φ
6.35mm
Φ
5
m
m
7
.
2
1
m
/
g
2
1
/
5
1
0
2
0
3
012
018
Model
(38QUS)
Summary of Contents for 38QUS012
Page 80: ......