Defrost Operation Correction Factor (F ); Correction Ratio Due To Humidity (Cr); Correction Factor According To Altitude - Hitachi UTOPIA R32 Series Technical Catalogue

4 Capacities and selection data
Defrost Operation correction factor (fD)
4.7 Defrost Operation correction factor (f
The heating capacity does not include operation during frost or defrosting.
When this type of operation is taken in account, the heating capacity must be corrected according to the following
equation:
Correction heating capacity = Correction factor x heating capacity
Outdoor inlet air temperature (ºC DB)
Correction factor
?
N O T E
• Defrost correction factor corresponds to a relative humidity of 85%.
If the condition changes, the correction factor will be different.
• Defrost correction factor is not valid for special conditions such as
during snow or operation in a transitional period.

4.8 Correction ratio due to humidity (CR)

The cooling capacity data for the outdoor units is taken from the cooling capacity tables. The tables are calculated on the
basis of a relative humidity of 50%.
In some situations, it's possible that the temperature condition of the ambient to be conditioned, specifies other different
relative humidity, which affect at the Dry Bulb temperature. In this cases, it's necessary to calculate the difference
between the indoor air inlet dry bulb temperature required by the system and the indoor air inlet dry bulb temperature
shown in the cooling capacity data.
This temperature difference requires an adjustment of the cooling capacity of the system.
Q =Q + (CR x (DB - DB))
AC C R
4.9 Correction factor according to altitude (f
The capacity is affected by the altitude of the installation location. When the altitude is above sea level, capacity must be
corrected with the altitude correction factor according to the following equation:
Correction capacity = Altitude Correction factor x Capacity
Altitude (m)
Correction factor
59 TCGB0136 rev.1 - 05/2021
D
-7 -5
0.95 0.93
Heating
capacity
Model
RAS-3HVRC2
RAS-4H(V)(R/N)(C/P)2E
RAS-5H(V)(R/N)(C/P)2E
RAS-6H(V)(R/N)(C/P)2E
0 300 600 900
1 0.97 0.94 0.90
)
-3 0 3
0.88 0.85 0.87
Reduced
capacity
due to frost
build-up
1 cycle
CR
0.34
0.43
0.51
0.59
)
AL
1200 1500 1800 2100
0.88 0.84 0.81 0.78
5 7
0.90 1.00
Time
Max. defrosting
2400 2700 3000
0.75 0.72 0.69
4