Sanyo SGP-E120J2GU2, User Manual

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Construction
E - 6
Nitrogen
Valves kept closed
Gage manifold
Gas side
Liquid side
1. Points regarding refrigerant piping construction
Caution
●
In order to prevent oxidizing films inside the piping, purge the piping with nitrogen.
●
Commercial anti-oxidants have adverse reactions on refrigerants and the refrigeration oil, so they should not
be used.
Fig. 5
5
Gas-tightness testing and evacuation
●
It is a requirement of the High Pressure Gas Safety Law to carry out a gas-tightness test on gas heat pump air
conditioning systems. Therefore, carry out the following points to verify that there are no leaks from the joints
in the piping.
●
After connecting the gage manifold to the service ports on both the gas pipe (thick pipe) and the
liquid pipe (thin pipe) sides, connect the nitrogen and vacuum pump as shown in Fig. 6.
● Raise the pressure to the testing level of
3.0MPa with nitrogen, and check for leaks.
Leakage of refrigerant can be the cause of
accidents due to lack of oxygen.
Caution
● After completing the gas-tightness test,
evacuate the indoor unit and the piping
down to 667Pa.
● After completing evacuation, do not leave it
for a long period of time.
（ Note ） Each service port has a check
valve.
(4)Adding additional refrigerant charge
The quantity of refrigerant charged at the time of shipping did not consider the length of piping. Add additional
refrigerant appropriate to the length of piping.
Weighing
scales
Gage manifold
Gas side
Liquid side
Pressure
regulator
Pressure meter
Siphon
pipe
Vacuum pump
Nitr
og
en
Refrigerant
container
Fig. 6