McQuay MDS030AR Applications Manual page 53

If we know the heat performance index q
calculate the heating load
as follows:
Where,
a is the correction factor. For details, see the table.
q is the heat performance index of the building. It is the heating load when the difference between
v
the indoor temperature and the outdoor temperature is 1 . For details, see the table.
V is the outside volume of the building. (Unit:m
(t -t ) is the calculated difference between the indoor and outdoor temperatures. (Unit: )
n w
Heating correction factor a:
Heating outdoor temperature
0
-5
-10
-15
-20
Heat performance index of the building
3 3
Building type V (10 m ) q
5
Office 5 10
building 11 15
15
5
Club 5 10
11
5
Hospital 6 10
11 15
16
5
6 10
Cinema 11 15
16 20
21 30
31
5
Public area 6 10
11
Notes
During selection, you must consider the following factors which affect the cooling and heating attenuation
and correction: 1) Length of the pipe connecting the indoor unit and outdoor unit; 2) Difference between the
actual ambient temperatures of the indoor/outdoor units and the rated working temperatures of the MDS
for cooling/heating.
If the heating pump system is selected according to the cooling load, you must verify its heating capacity.
Especially in the areas north to Yellow River, inadequate heating capacity must be compensated
with a model with an auxiliary electric heater or hot-water coil pipe.
The MDS unit is designed according to GB/T 18837-2002. There is a negative difference of about 5% between
the actual cooling capacity and the rated capacity. Therefore, you must fully consider this factor during selection
and ensure certain cooling capacity factor.
[W/(m
v
Q = aq
total
a Heating outdoor temperature
2.05
1.67
1.45
1.29
1.17
Building type
3
W/m t
v n
0.6
0.53 18 Workshop
0.49
0.56
0.72
0.65 16 Equipment
0.58
0.81
0.75 20
Auxiliary room
0.67
0.64
0.92
0.82
Fire engine
0.79 14
0.70
0.65
0.61
1.22
1.14 14 Bathroom
1.05
Design & installation Guide For McQuay MDS Multi System
3
. )] and outside volume V (m
V( t t )
v n w
2
)
-25
-30
-35
-40
3 3
V(10 m ) q
5 10
11 20
21 30
31
0.5
0.6 1.0
room 1.1 2.0
2.1
0.5
0.6 1.0
1.1 2.0
2.1
2.0
2.1 5.1
5.1
house
5.0
5.1 10.0
10
3
), we can
a
1.08
1.00
0.95
0.9
3
W/m t
v n
3.38
2.73 14
2.04
1.45
2.30
0.82 12
0.71
0.50
0.83
0.72 18
0.56
0.51
0.72
0.63 15
0.60
1.49
1.38 25
1.25
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