Carrier 48HC D17 Series Service And Maintenance Instructions page 21

SIZE DESIGNATION
17
20
24
28
EXAMPLE:
Model 48HC*D28
Circuit A
Outdoor Temperature . . . . . . . . . . . . . . . . . .
Suction Pressure . . . . . . . . . . . . . . . . .
Suction Temperature should be
Circuit B
Outdoor Temperature . . . . . . . . . . . . . . . . . .
Suction Pressure . . . . . . . . . . . . . . . . .
Suction Temperature should be
Using The Cooling Charging Charts
Take the outdoor ambient temperature and read the
suction pressure gauge. Refer to chart to determine what
suction temperature should be. If suction temperature is
high, add refrigerant.
NOMINAL TON
REFERENCE
15
17.5
20
25
85_F (29_C)
125 psig (862 kPa)
. . . . . . . . . . 63_F (17_C)
85_F (29_C)
120 psig (827 kPa)
. . . . . . . . . . 58_F (14_C)
If suction temperature is low, carefully recover some of
the charge. Recheck the suction pressure as charge is
adjusted.
Select the appropriate unit charging chart from Fig. 25,
26, 27, 28, 29 30 31 and 32.
Take the outdoor ambient temperature and read the
suction pressure gauge. Refer to chart to determine what
suction temperature should be. If suction temperature is
high, add refrigerant. If suction temperature is low,
carefully recover some of the charge. Recheck the suction
pressure as charge is adjusted.
For 17- - 28 sizes, perform this procedure once for Circuit
A (using the Circuit A chart) and once for Circuit B (using
the Circuit B chart).
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