DC Inverter U-match Series Floor Ceiling Type Unit
16
(2). If the outdoor unit is installed higher
than the indoor unit
1). Wrap tape from the lower end working
up.
2). All pipes must be bound and taped
together. A trap must be installed to
prevent water from returning to the
room (See Fig. 4.16).
3).
Attach all pipes to the wall with
clamps/saddles.
Fig. 4.16
4.4 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!
4.4.1 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
. 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. 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, 20
minutes for the 18k units, 30 minutes for the 24k/30k/36k units, 45 minutes
for the 42k/48k units. Verify that the pressure gauge at the low pressure
side of the manifold valve assembly reads -1.0MPa (145psig)
. If it doesn’t
, it
indicates there is leak somewhere. If that is the case, close the switch fully,
and stop the vacuum pump.
(6). Wait for some time to see if the system pressure can remain unchanged, 3
minutes for the 18k/24k units, 10 minutes for the 30k/36k/42k/48k units.
