Correcting Cooling And Heating Capacity - Mitsubishi Electric MXZ-4C36NAHZ Service Manual

4-4. CORRECTING COOLING AND HEATING CAPACITY

4-4-1. Correcting Changes in Air Conditions
(1)To obtain the system cooling and heating capacity and the electrical characteristics of the outdoor unit, first add up the
ratings of all the indoor units connected to the outdoor unit (see table below), and then use this total to find the standard
capacity with the help of the tables on "4-3. STANDARD CAPACITY DIAGRAM".
• Standard conditions:
Rated cooling capacity
Rated heating capacity
• Use the rated capacity and rated input given in "4-3. STANDARD CAPACITY DIAGRAM".
• The input is the single value on the side of the outdoor unit; the input on the sides of each indoor unit must be added to
obtain the total input.
(2)The capacity of each indoor unit may be obtained by multiplying the total capacity obtained in (1) by the ratio between the
individual capacity at the rated time and the total capacity at the rated time.
Individual capacity under stated conditions =Total capacity under the stated conditions o
(3) Capacity correction factor curve
Fig. 1-1: Cooling capacity
(MXZ-8C48NA, MXZ-8C48/5C42/4C36NAHZ)
1.4
1.3
24(75.2)
1.2
22(71.6)
20(68.0)
1.1
19(66.2)
1.0
18(64.4)
0.9
0.8
16(60.8)
0.7
0.6 Indoor intake air wet-bulb temperature <:W.B. (°F W.B.)>
0.5
–5 –10 –5 0 5 10
5 14 23 32 41 50
Outdoor intake air dry-bulb temperature
Fig. 2-1: Heating capacity (MXZ-8C48NA)
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
Indoor intake air dry-bulb temperature <:D.B.(°F W.B.)>
0.4
−20 −15 −10 −5
−4 5 14 23
Outdoor intake air dry-bulb temperature
Note: These diagrams show the case where the operation frequency of a compressor is fixed.
OCH573
Indoor
Outdoor D.B. 95°F
Indoor
Outdoor D.B. 47°F / W.B. 43°F
15 20 25 30 35 40 45 (°C W.B.)
59 68 77 86 95 10 11 (°F W.B.)
16.0(60.8)
21.0(69.8)
26.0(78.8)
0 5 10 15 (°C W.B.)
32 41 50 59 (°F W.B.)
D.B. 80°F / W.B. 67°F
D.B. 70°F
Fig. 1-2: Cooling input
(MXZ-8C48NA, MXZ-8C48/5C42/4C36NAHZ)
1.4
Indoor intake air wet-bulb temperature <:W.B. (°F W.B.)>
1.2
1.0
0.8
0.6
0.4
0.2
–15 –10 –5 0 5
5 14 23 32 41
Outdoor intake air dry-bulb temperature
Fig. 2-2: Heating input (MXZ-8C48NA)
1.4
1.2
1.0
0.8
0.6
0.4
0.2
Indoor intake air dry-bulb temperature <:D.B.(°F W.B.)>
0.0
−20 −15 −10
−4 5 14
Outdoor intake air dry-bulb temperature
20
Individual capacity at the rated time
Total capacity at the rated time
20(68.0)
22(71.6)
24(75.2)
19(66.2)
18(64.4)
16(60.8)
10 15 20 25 30 35
50 59 68 77 86 95
16.0(60.8)
21.0(69.8)
26.0(78.8)
−5 0 5 10
23 32 41 50
40 45(°C W.B.)
10 11 (°F W.B.)
15 (°C W.B.)
59 (°F W.B.)