McQuay AGR 080AS Product Manual

12
AGR 070A through 100A Product Manual AGR-3
Selection example
Given:
64 tons required capacity
95°F ambient temperature
Cool 154 gpm from 54
°
F to 44°F
0.0001 evaporator fouling factor
2,000 foot altitude
Add 3% to the required capacity for approximate derate: 64 x 1.03 = 66 tons. From Performance Table
9, an AGR-070AM at the given conditions will produce 67.5 tons with a compressor kW input of 77.1
and a unit EER of 9.6.
1. Determine derate factors :
Altitude correction from Table 3: 0.986 Capacity, 1.009 Power
2. Piping correction:
Assume 2 1/8" suction line based on connection size in Table 6
(3) 90
°
Standard ells (Table 4) 3 x 5 ft =15 ft
Plus actual linear feet 70 ft
Total Equivalent Feet 85 ft
Check Table 7 for size and find that 2 1/8” is acceptable size for oil carry. If the selected riser size
is too large, double risers would be required. See Refrigerant Piping section for important
information, including double riser layouts.
The capacity correction factor from Table 8 is 0.984.
3. The corrected capacity of the AGR is: 67.5 tons x 0.986{altitude} x 0.984{piping} = 65.5 tons
This satisfies the 64 ton requirement.
4. Correct the compressor power required: 77.1 kW x 1.009{altitude} = 77.8 kW.
5. Calculate the unit power input from corrected EER:
W = BTU / EER W =65.5 tons x 12,000 / (9.6 EER / 1.009) = 81.1 kW
6. Determine the evaporator pressure drop. Enter the pressure drop curves (Figure 9) at 154 gpm and
read up to AGR 070AM, read over to pressure drop of 15 ft.
Selection example using ethylene glycol
Given: 64 tons required capacity
95
°
F ambient temperature
54
°
F to 44
°
F chilled fluid
0.0001 fouling factor
Protect from freezing down to 0°F
1. From Table 1, select an ethylene glycol concentration of 40% to protect against freezing at 0°F.
2. At 40% ethylene glycol, the adjustment factors are: Capacity =0.961, kW = 0.976,
Flow = 1.121, pressure drop = 1.263
3. Select the AGR 070AM and correct with 40% ethylene glycol factors and piping correction factor.
4. Correct capacity = 0.961 X 67.5 tons = 64.6 tons
5. Correct compressor kW = 0.976 X 77.1 = 75.2 kW
Figure 5, Sample Piping Layout
A
GR-AM
Remote Eva
p
orator
10 ft.
30 ft.
20 ft.
10 ft.
Li
q
uid
Line
Suction
Line

McQuay AGR 080AS Specifications

General

Brand	McQuay
Model	AGR 080AS
Category	Chiller
Language	English