Mitsubishi Electric CITY MULTI PUMY-P200YKM3, Руководство по обслуживанию

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OCH791 _12
5 DATA
5-1. Selection of indoor and outdoor units
5-1-1. Cooling
Design condition
Outdoor dry bulb temperature 38ºC
Total cooling load 19.4 kW
Room 1 Indoor dry bulb temperature 27ºC
Indoor wet bulb temperature 20ºC
Cooling load 9.1 kW
Room 2 Indoor dry bulb temperature 24ºC
Indoor wet bulb temperature 18ºC
Cooling load 10.3 kW
Other Indoor/Outdoor piping equivalent length 40 m
Capacity of indoor unit
P·FY series Model class of indoor unit 10 15
— 20 — 25 32 — 40 — 50 — 63 71 80 100 125 140 200
Model capacity (kW)
1.2 1.7 — 2.2 — 2.8 3.6 — 4.5 — 5.6 — 7.1 8.0 9.0 11.2 14.0 16.0 22.4
M series
S series
P series
Model class of indoor unit
— 15 — 20 22 25 — 35 — 42 50 60 — 71 — 100 — — —
Model capacity (kW)
— 1.5 — 2.0 2.2 2.5 — 3.5 — 4.2 5.0 6.0 — 7.1 — 10.0 — — —
■ Cooling calculation
• Tentative selection of indoor units
Room1: PEFY-P80 9.0 kW (Rated)
Room2: PEFY-P100 11.2 kW (Rated)
In this case, the total capacity is 20.2. (9.0 + 11.2 = 20.2)
• Tentative selection of outdoor unit
Proper outdoor unit in this case is P200 as the total capacity of the indoor units is 20.2.
PUMY-P200 22.4 kW (Rated)
• Calculation for the corrected capacity of the total indoor units (CTi)
Correction factor for indoor design wet bulb temperature: Room 1 (20°C) 1.03 (Refer to Figure 1.)
Room 2 (18°C) 0.94 (Refer to Figure 1.)
CTi = Σ (Rated capacity of indoor unit × Correction factor for indoor temperature)
= 9.0 × 1.03 + 11.2 × 0.94
= 19.8 kW
• Calculation for the corrected capacity of the outdoor unit (CTo)
Correction factor for outdoor temperature (38°C) 0.96 (Refer to Figure 2.)
Correction factor for piping length (40 m) 0.91 (Refer to "Correcting Capacity".)
CTo = Rated capacity of outdoor unit × Correction factor for outdoor temperature × Correction factor for piping length
= 22.4 × 0.96 × 0.91
= 19.6 kW
• Determination of maximum system capacity (CTx)
Comparison between CTi and CTo:
CTi = 19.8 > CTo = 19.6, thus, select CTo.
CTx = CTo = 19.6 kW
• Comparison with essential load
Against the essential load 19.4 kW, the maximum system capacity is 19.6 kW: A proper outdoor unit is selected.
• Calculation for the maximum indoor unit capacity of each room
When CTx = CTo, use the calculation formula below.
Room1: CTx × Corrected capacity for Room1/CTi
= 19.6 × (9.0 × 1.03)/19.8
= 9.2 kW
The capacity is enough for the cooling load of Room 1 (9.1 kW): A proper indoor unit is selected.
Room2: CTx × Corrected capacity for Room2/CTi
= 19.6 × (11.2 × 0.94)/19.8
= 10.4 kW
The capacity is enough for the cooling load of Room 2 (10.3 kW): A proper indoor unit is selected.
Note:
• If CTx = CTi, refer to the calculation formula in "Heating" to calculate the maximum indoor unit capacity of each
room.
• Go on to the selection of units for heating after the selection for cooling has successfully completed. If failed, try
again until proper units are selected.