Mitsubishi Electric MXZ-SM72TAM-U1 Service Manual page 14

■ How to determine the capacity when greater than 100% indoor model size units are connected in
total
The purpose of this flow chart is to select the indoor and outdoor units. For other purposes, this flow chart is intended
only for reference.
Determine the load (L) and the indoor/outdoor temperature.
Temporarily select the indoor/outdoor units.
Indoor Unit
Total indoor units capacity (CT
Outdoor Unit
Outdoor unit capacity (CT
Maximum capacity (CT
Individual indoor unit capacity: CT
Average indoor temp. power input Coef. (C
Outdoor unit input = Nominal outdoor unit input ×
OCH800A_14
Reselect the indoor units
Reselect the outdoor units
n
) = (Individual nominal (rated) indoor unit capacity CT
i
k=1
Individual indoor temperature correction coef. α
(Figure 1, 4)
n: Total number of indoor units
k: Indoor unit number
) = Nominal outdoor unit capacity × G (CT
o
Outdoor temperature correction coef. (Figure 2, 5) ×
Piping length correction coef. (Figure 3, 6) ×
Defrost correction coef.
(In heating operation, Table 1)
G (x) is the approximate correction function
when greater than 100% model size units
are connected.
G (x) refers to "Standard capacity diagram".
No
CT ≤ CT
o i
Yes
) = CT
max o
No
L ≤ CT
o
Yes
Yes
Want to change to
smaller indoor units?
No
CT × α
n
= CT ×
(CT × α )
ik max
m=1
No
Does it fulfill the load of
each room?
Yes
Selecting units is completed.
c : Outdoor unit power input coef. of k indoor unit room temp.
k
(Refer to 4-2.)
M : Number part of the k indoor unit model (e.g. P80 → 80)
k
)
ave
n
{C × (M / M )}
C = k k
ave
k=1
k=1
C × F (CT )
ave i
F (x) is the approximate correction function when greater than 100%
model size units are input as connected.
×
ik
)
k
)
i
ik
k
im m
Average indoor temp. power input Coef. (C
n
k
Outdoor unit input = Nominal outdoor unit input ×
Maximum capacity (CT ) = CT
max i
No
L ≤ CT
i
Yes
Yes
Need to select smaller
outdoor units?
No
No
Does it fulfill the load of
each room?
Yes
Selecting units is completed.
Nominal outdoor unit capacity
< Total indoor units capacity
Yes
Outdoor unit input
= Nominal outdoor unit input ×
Outdoor temperature correc-
tion coef. × ƒ(CT
ƒ(x) is the approximate correction
function when less than or equal 100%
model size units are input as connected.
)
ave
n n
{C × (M / M )}
C = k k
ave
k=1
k=1
C × F (CT )
ave i
Capacity
Determination
No
)
i
k
Input
Calculation