Midea MV8M-120WV2RN1 Engineering Data page 55

8.4 Capacity Correction Factors for Frost Accumulation
The heating capacity tables do not take account of the reduction in capacity when frost has accumulated or while the
defrosting operation is in progress. If snow has accumulated against the outside surface of the outdoor unit heat exchanger
heating capacity is reduced. The reduction in heating capacity is dependent on a number of factors including the outdoor
temperature, the relative humidity and the amount of frosting which has occurred.
Corrected heating capacity values, which take these factors into account, can be calculated as follows, using the correction
factors for frost accumulation given in Table 2-8.7:
Corrected heating capacity = Value given in outdoor heating capacity table × Correction factor for frost accumulation
Table 2-8.7: Correction factor for frost accumulation
Heat exchanger inlet port temperature (
Correction factor for frost accumulation
Corrected heating capacities express the heating capacity over the heating/defrosting cycle shown in Figure 2-8.7.
/ RH 85%)
°C
80/120/140 model
100/160 model
Figure 2-8.7: Defrosting cycle
V8 Mini R410A VRF 50Hz
-7 -5 -2 0
0.88 0.87 0.85 0.8
0.85 0.84 0.82 0.77
2 5 7
0.83 0.91 1
0.8 0.88 1
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