Gree GMV-ND22PHS/B-T Owner's Manual page 15

(11) Drain pipes should have a downward slope of at least 1%~2%, in order to prevent pipes
from sagging, install hanger bracket at intervals of 1000~1500mm.
4.3.3 Test of Drainage System
(1) Please test drainage system after electric work is finished.
Inject approximately 1L purified water to drain pan from air vent, ensure that not to splash
the water over the electrical components (e.g. water pump. etc.).
1) In case of commissioning finished, please energize the IDUs and switch to cooling or
dry mode, meanwhile, the water pump operates, you can check the draining through
the transparent part of drain socket.
2) If communication wire is not connected, communication malfunction "C0" will occur
after 60s of energizing. In this case, the water pump operates automatically. Check if
the water pump drains normally drains normally through drainage port. The water
pump will stop automatically after running for 10min.
(2) During the test, please carefully check the drainage joint, make sure no any leakage
occur.
(3) It is strongly recommend to do the drain test before ceiling decoration.
Multi Variable Air Conditioners Ducted Type Indoor Unit
Fig 4.3.10
Fig 4.3.11
Fig 4.3.12
12