Page 8
IM-800
CHARGE CHECKS
Capillary Tube/Fixed Orifice System
1. Fully open both base valves.
2. Connect service gauge manifold to base-valve service ports
to purge lines. Run system at least 10 minutes to allow
pressure to stabilize.
3. Temporarily install thermometer on suction (large) line
near condensing unit. Provide good contact between the
thermometer and line. Wrap thermometer with insulating
material to provide an accurate reading.
4. Refer to Table 3 for proper system superheat. Add charge
to lower superheat. Remove charge to raise superheat.
5. Remove gauge lines carefully.
Table 3: System Superheat
Superheat Determination
1. Read suction pressure. Using Table 4, determine saturated
suction temperature.
2. Read suction line temperature.
3. Use the following formula to determine superheat:
Superheat = Suction Line Temp. - Saturated Suction Temp.
Table 4:
Saturated Suction Pressure (R-22)
Expansion Valve System
1. Fully open both base valves.
2. Connect service gauge manifold to base-valve service parts
making sure lines are purged. Run system at least 10 min-
utes to allow pressure to stabalize.
3. Temporarily install the thermometer to liquid (small) line
near condensing unit. Provide good contact between ther-
mometer and line. Wrap thermometer with insulating
material to provide an accurate reading.
4. Referring to Table 5, adjust charge to obtain a temperature
12-15°F below the saturated liquid temperature.
Example:
If the Liquid Pressure is 260 psig then the Saturated Tempera-
ture will be 120°F. Adjust the Saturated Temperature by sub-
tracting 12-15°F. This will give you a Liquid Line
Temperature of 105° - 108°F.
Table 5: Saturated LIquid Temperature
SPECIAL NOTE:
For systems with more than 15’ of inter-
connecting tubing, please refer to Table 6 for line charge
allowance per foot of tubing.
Table 6: Line Charge Allowance (R-22 - oz./ft.)
NOTE:
Systems with over 50’ separation between condens-
ing unit and evaporator may require oil charge adjustment
(Table 7).
Table 7: Oil Charge Adjustment
*Use either Texaco WF-32 (formerly cappella B) or Suniso 3G-S oil.
C
WARNING
Escaping liquid refrigerant can cause burns. Wear
protective gloves, gear and eyewear.
AMBIENT CONDENSER INLET
TEMPERATURE (
o
F DB)
RETURN AIR
TEMPERATURE (
o
F DB)
65
70
75
80
85
100
5
5
95
5
7
9
90
7
12
18
85
5
10
17
20
80
5
12
21
26
75
5
10
17
25
29
70
5
14
20
28
32
65
13
19
26
32
35
60
17
25
30
33
37
SUCTION PRESSURE PSIG
SATURATED SUCTION
TEMPERATURE
o
F
50
26
53
28
55
30
58
32
61
34
63
36
66
38
69
40
72
42
75
44
78
46
81
48
LIQUID PRESSURE PSIG
SATURATED TEMPERATURE
o
F
200
102
210
105
220
108
230
111
240
114
250
117
260
120
270
123
280
126
290
128
300
131
LINE O.D. (IN)
LIQUID LINE
SUCTION LINE
1/4
0.22
3/8
0.58
1/2
1.14
5/8
1.86
0.04
3/4
0.06
7/8
0.08
1 1/8
0.15
1 3/8
0.22
UNIT MODEL
(TONS)
ADDITIONAL OIL CHARGE PER EACH ADDI-
TIONAL 10’ OF LINE (OZ)*
1 - 1 1/2
0.25
2 - 5
0.5
Содержание ACU018ARAY
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