Sanyo SGP-M2 Procedimientos Y Puntos Técnicos Para La Instalación Del Sistema página 34

3-4. Tubing airtightness test and vacuum application
An airtightness test is required for gas heat pump A/C as part of industry installation guidelines. Follow the
procedure below to perform the test and confi rm there is no leakage from any connections.
Connect the manifold gauge to both service ports - on the wide tube side and narrow tube size. Then con-
nect the nitrogen tank, vacuum pump, and other items as shown in Fig. 17.
When performing airtightness tests or creating vacuums, perform them for all service ports simultaneously.
(All outdoor unit valves should remain closed.)
Always use nitrogen for the airtightness test. (Do not use oxygen, carbon dioxide, other refrigerants, etc.)
When performing the airtightness test for newly installed indoor/outdoor unit tubing, we recommend testing
the tubes separately before connecting them to outdoor units.
The service ports are check valves.
Use nitrogen to raise the pressure to the airtightness test pressure (4.15 MPaG)
and confi rm that there is no leakage. Refrigerant leakage can cause suffocation
and injury to nearby persons.
After the airtightness test is completed, apply vacuum of 667 Pa (-755 mmHg, 5 Torr) or below to the in-
door unit and tubing.
Do not leave for a long period of time after the vacuum state has been reached.
Pressure gauge
Siphon tube
Vacuum pump
Weight scale
Fig. 17
GB - 34
Pressure reducing valve
Refrigerant container
R410A