If the outdoor unit is installed higher than the
indoor unit (See Fig.16)
(1). Taping should be done from lower to the
upper part.
(2). All pipes are bound and taped together
and also should be trapped to prevent
water from returning to the room.
(3). Restraint all pipes to the wall with
saddles.
5.3 Vacuum and Gas Leakage Inspection
Do not purge the air with refrigerants but use a vacuum pump to vacuum the installation! There is no
extra refrigerant in the outdoor unit for air purging!
5.3.1 Vacuum
(1). Remove the caps of the liquid valve, gas valve and also the service port.
(2). Connect the hose at the low pressure side of the manifold valve assembly to the service
port of the unit's gas valve, and meanwhile the gas and liquid valves should be kept closed
in case of refrigerant leak.
(3). Connect the hose used for evacuation to the vacuum pump.
(4). Open the switch at the lower pressure side of the manifold valve assembly and start the
vacuum pump. Meanwhile, the switch at the high pressure side of the manifold valve
assembly should be kept closed, otherwise evacuation would fail.
(5). The evacuation duration depends on the unit's capacity, generally, 15 minutes for the 12k
units, 20 minutes for the 18k units, 30 minutes for the 24 units. And verify if the pressure
gauge at the low pressure side of the manifold valve assembly reads -1.0Mp (-75cmHg),
if not, it indicates there is leak somewhere. Then, close the switch fully and then stop the
vacuum pump.
(6). Wait for some time to see if the system pressure can remain unchanged, 3 minutes for the
units less than 18k, 5 minutes for the 18K~24k units. During this time, the reading of the
pressure gauge at the low pressure side can not be larger than 0.005Mp (0.38cmHg).
DC Inverter Free match Series Cassette Type Unit
CAUTION!
20
Trap
Fig.16