TOSOT DC INVERTER U-MATCH AIR
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(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. And verify if the pressure gauge
at the low pressure side of the manifold valve assembly reads -0.1MPa (-750mmHg), if not, it
indicates there is leak somewhere. Then, close the switch fully and then stop the vacuum pump.
(6) Wait for 10min to see if the system pressure can remain unchanged. If the pressure increase, there
may be leakage.
(7) Slightly open the liquid valve and let some refrigerant go to the connection pipe to balance the
pressure inside and outside of the connection pipe, so that air will not come into the connection pipe
when removing the hose. Note that the gas and liquid valve can be opened fully only after the
manifold valve assembly is removed.
(8) Place back the caps of the liquid valve, gas valve and also the service port.
.
Figure 3-2-4
NOTICE
: For the large-sized unit, it has the service port for both the gas valve and the liquid valve.
During evacuation, it is available to connect two hoses of the manifold valve assembly to two service
ports to quicken the evacuating speed.
3.1.7.2 Additional Charge
Refrigerant suitable for a piping length of 7.6m (25feet) is charged in the outdoor unit at the factory.
When the piping is longer than 7.6m (25feet), additional charging is necessary.
For the additional amount, see Table 3-2-3.
Table 3-2-3
Item
Model
Additional Refrigerant Amount for Extra Pipe
18k
33g per 1.5m (1.2 ounce per 5 feet )
24k~48k
81g per 1.5m (2.9 ounce per 5 feet )
When the height difference between the indoor unit and outdoor unit is larger than 10m (32-4/5feet),
an oil bend should be employed for every 6m (19-2/3 feet).
