Trane Precedent YSC060-120, Руководство пользователя

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RT-PRC017-EN
Selection
Procedures - IP Units
Cooling Capacity
Step 1 — Calculate the building’s total
and sensible cooling loads at design
conditions. Use the Trane calculation
form or any other standard accepted
method.
Example: The following are the building
cooling requirements:
a. Electrical Characteristics: 380-415/50/3
b. Summer Design Conditions: Entering
Evaporator Coil: 80° DB/ 67° WB
Outdoor Ambient: 95°
c. Total Cooling Load: 58 MBh
d. Sensible Cooling Load: 42 MBh
e. Airflow: 2000 cfm External Static
Pressure: .6 in wg
f. Downflow Configuration
Step 2 — Size the equipment using Table
PD-1a to match the cooling loads at
design conditions.
Table PD-1a shows that a YSC060AD has
a gross cooling capacity of 62.0 MBh and
46.4 MBh sensible capacity at 95 DB
ambient and 2000 cfm with 80 DB/ 67
WB air entering the evaporator.
Use the following formula to calculate
fan motor heat, which can be found in
the notes in Table PD-8a:
Fan motor heat (MBh) =
2.915 x (Fan bhp) + 0.451
For example: With 2000 cfm and 0.60
inches, specified by the engineer, Table
PD-8a shows 1.06 bhp for a high heat
model.
Fan motor heat =
2.915 x 1.06 + 0.451 = 3.5 MBh
Net Total Cooling =
62.0 MBh - 3.5 = 58.5 MBh
Net Sensible Cooling Capacity
46.4 MBh - 3.5 = 42.9 MBh.
Heating Capacity
Step 1 — Calculate the building heating
load using the Trane calculation form or
other standard accepted method.
Step 2 — Size the system heating
capacity to match the calculated building
heating load. The following are building
heating requirements:
a. Total heating load of 70.0 MBh
b. 2000 cfm
c. Fuel - Natural gas
For the YSC060AD there are two heating
capacities available, 67 MBh and 100
MBh input models shown in Table PD-
32. The output capacities of these
furnaces are 54 MBh and 80 MBh
respectively. The high heat model with
80 MBh best matches the building
requirements, indicating a YSC060AD*H
should be selected.
Air Delivery Selection
External static pressure drop through the
air distribution system has been
calculated to be 0.6 inches of water. Enter
Table PD-8a for a YSC060AD*H at 2000
cfm and 0.60 static pressure. The
standard motor will give the desired
airflow.
Accessory Selection
Select accessories needed to
accommodate the application.