Gree FP-22LM/D-K - Design and Selection; Selection Principle; Selection Steps; Example for Selection

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Design and Selection
DESIGN AND SELECTION
1 Selection principle
1.1 Selection steps
(1) If the external static pressure is 0Pa, the unit cannot be connected with ducts.
(2) Select the unit type based on the air ow, cooling capacity and heating capacity.
(3) Select the unit model based on the indoor cooling/heating load, inlet air DB/WB temperature,
entering water temperature and related data sheets. The cooling/heating capacity of the selected
unit should be or larger than the indoor cold/heat load.
(4) Take consideration of sound level.
According to the allowable sound level of the corresponding building (as shown in the table below for
reference), check if the selected unit can meet the sound requirement.
Allowed sound level
Type of buildings A-weighted sound level dB(A)
Recording studio, broadcast studio, dubbing room 20~25
Concert hall, theatre, television studio 25~30
Cinema, lecture theatre, meeting room 30~35
Ofce room, design ofce, reading room 35~40
Restaurant, banquet hall, gym, hotel 40~50
Waiting room, shopping center 45~55
Cleaning room, ofce room with mechanical appliance 55~65
It is cited from
Practical Design Manual of Heating Air Conditioning
. If undesirable; reselect the unit
with lower sound level.
1.2 Example for selection
For a room of a hotel, the cooling load is 3090W, the inlet air dry bulb temperature is 27°C, the inlet
air wet bulb temperature is 19°C, the air ow is 600m
3
/h, the entering water temperature is 7°C and the
leaving water temperature is 12°C; the heating load is 3800W, the inlet air dry bulb temperature is 20°C,
the inlet air wet bulb temperature is no more than 15°C, the entering water temperature is 45°C and the
leaving water temperature is 40°C. Based on these conditions, select a proper FCU.
Step 1: Select the unit type based on the air ow, cooling capacity and heating capacity.
(1) Select the unit model based on the maximum cooling load.
(2) Select the cooling capacity at the high air ow to meet the average cooling load.
(3) In light of working conditions, the cooling capacity selected from the data sheet is equal to or larger
than the cooling load.
(4) When the cooling capacity is selected based on the medium or low speed air ow, then at specic
or load peak, use the high-speed for meeting the load demand.
(5) For the selected FP-68 in light of loads, its data sheet shows that the cooling capacity is 3200W,
heating capacity is 3800W and the air ow is 680m
3
/h.
(6) When the entering water temperature is 60°C, the heating capacity is 7000W, which meets the load
demand.