Gree GMV MTAC VRF Series, Service Manual

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Gree GMV MTAC VRF for North America
6
Below table shows the capacity variance ratio for 100% full load in standard working condition
(thermostat setting is 16°C(61°F ) for cooling and 30°C(86°F ) for heating).
50
40
30
20
Hp(m)
L(m) L(m)
Hm(m)
10
10
1.
0
1.
0
0.
99
0.
97
0.
95
0.
97
0.
95
0.
93
0.
89
0.
91
0.
87
20 30 40 50 60 70 80 90 100 110 120130140150
10 20 30 40 50 60 70 80 90 100 110 120130140150
0
10
20
30
40
50
40
30
20
Hp(m)
Hm(m)
10
0
10
20
30
40
Change rate of cooling capacity Change rate of heating capacity
Variance ratio of heating capacity
NOTICE!
m 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
ft 0 33 66 98 131 164 197 230 262 295 328 361 394 427 459 492
5 Principal of Operation
Components in flowcharts are presented according to the following table:
Name Compressor 4-way valve
Cut-off
valve
One-way valve Capillary tube
Symbol
Name
Gas-liquid
separator
Pressure
switch
Pressure
sensor
Axial-flow finned heat
exchanger
Electronic expansion valve
Symbol
In cooling, the low-temperature and low-pressure refrigerant gas from each indoor heat
exchanger will be merged and inhaled by the compressor and then become high-temperature and
high-pressure gas, which will later be discharged into outdoor heat exchangers. By exchanging
heat with outdoor air, refrigerant will turn to liquid and flow to each indoor unit via Y-type branch or
manifold. Pressure and temperature of the refrigerant will then be lowered by throttle elements
before it flows into indoor heat exchangers. After exchanging heat with indoor air, refrigerant wil
become low-temperature and low-pressure gas again and repeat the circulation so as to realize
the cooling effect. In heating, 4-way valve will be energized to make refrigerant circulate in a
reverse direction of cooling. Refrigerant will release heat in indoor heat exchangers (electric
heating elements will also work under certain circumstance and release heat) and absorb heat in
outdoor heat exchangers circularly so as to realize the heating effect.