128
Appendix
B. Suggested Capillary Tube Data for Air
Conditioning (R-22) Applications
The suggested capillary size is based on a condens-
ing temperature of 130°F, with 115°F liquid enter-
ing the capillary, 65°F gas entering the compressor.
Example No. 1 (See Table A-3)
Select the capillary required for a Tecumseh com-
pressor AH5540E rated 40,000 BTU/Hr.
Assuming a 3/8” OD tube coil, the maximum load
per circuit is 7000 BTU/Hr. or 40,000 ÷ 7000 or six
circuits. The load per circuit then becomes 40,000 ÷
6 or 6700 BTU per circuit.
a. For each circuit the capillary would be 35” x
.049 or 65” x .054.
b. As an option two capillaries could be used
to distribute into six circuits in the coil. The
load per capillary becomes 40,000 ÷ 2 or
20,000 BTU/Hr. The capillary is 40” x .080
or 58” x .085.
Example No. 2 (See Table A-3)
Select the capillary required for a Tecumseh com-
pressor AG5561E rated 61,000 BTU/Hr.
Assuming a 3/8” OD tube coil, the maximum load
per circuit is 7000 BTU/Hr. or 61,000 ÷ 7,000 or
8.7 circuits (use 10). The loading per circuit
becomes 6100 BTU/Hr. Use 40” x .049 or 75” x
.054 if the intention is to feed each circuit with a
separate cap tube. Fewer number of cap tubes are
optional of course.
Assuming a 1/2” OD tube coil, the maximum load
per circuit is 14,000 BTU/Hr. or 61,000 ÷ 14,000
or 4.4 circuits. Use five circuits, 61,000 ÷ 5 or 12,
200 BTU/Hr. per circuit. Use 40” x .064 or 68” x
.070 if the intention is to feed each circuit with a
separate cap tube. Fewer number of cap tubes are
optional, of course.
Table A-3: R-22 Capillary Tube Data
Compressor
Capacity
BTU/Hr.
No. of
Capillaries
Capillary Size
Coil Circuits
(For Acceptable Pressure Drop)
Short
Long
3/8” Tube
1/2” Tube
4500
1
36” x .042
80” x .049
1
5000
1
25” x .042
64” x .049
1
5500
1
20” x .042
52” x .049
1
6000
1
40” x .049
75” x .054
1
6500
1
35” x .049
65” x .054
1
7000
1
28” x .049
52” x .054
1
8000
1
36” x .054
65” x .059
1
9000
1
28” x .054
48” x .059
2
1
10000
1
36” x .059
64” x .064
2
1
11000
1
28” x .059
50” x .064
2
1
12000
1
40” x .064
68” x .070
2
1
13000
1
32” x .064
56” x .070
2
1
14000
1
44” x .070
70” x .075
2
1
15000
1
36” x .070
56” x .075
3
2
16000
1
30” x .070
48” x .075
3
2
17000
1
38” x .075
65” x .080
3
2
18000
1
35” x .075
55” x .080
3
2
19000
1
28” x .075
48” x .080
3
2
20000
1
40” x .080
58” x .085
3
2