Evaporator Temp = 5°C | Condenser Temp = 50°C
| D/L (in/m/ft) | 0.047 in | 0.049 in | 0.055 in | 0.059 in | 0.063 in | 0.071 in | 0.079 in | 0.087 in |
|---|---|---|---|---|---|---|---|---|
| 8000 BTU/H | 0.3959 m / 1.30 ft | 0.5078 m / 1.67 ft | 1.006 m / 3.30 ft | 1.505 m / 4.94 ft | 2.169 m / 7.12 ft | 4.091 m / 13.42 ft | ||
| 12000 BTU/H | 0.2033 m / 0.67 ft | 0.2438 m / 0.80 ft | 0.4583 m / 1.50 ft | 0.6953 m / 2.28 ft | 1.025 m / 3.36 ft | 2.041 m / 6.70 ft | 3.646 m / 11.96 ft | 6.012 m / 19.73 ft |
| 18000 BTU/H | 0.2097 m / 0.69 ft | 0.2568 m / 0.84 ft | 0.3472 m / 1.14 ft | 0.6855 m / 2.25 ft | 1.295 m / 4.25 ft | 2.267 m / 7.44 ft | ||
| 24000 BTU/H | 0.2479 m / 0.81 ft | 0.3682 m / 1.21 ft | 0.6588 m / 2.16 ft | 1.17 m / 3.84 ft |
Note: Preferred values are underlined for better guidance.
36000 BTU/H
- Diameter: 0.098 in
- Length: 0.9151 m / 3.00 ft
Recommendations for Selecting Capillary Tubes in Air Conditioners Using R410A Refrigerant
The performance of capillary tubes in air conditioners depends on both their length and diameter, as these factors determine the total restriction:
- Impact of Diameter and Length:
- A change in diameter, even by a small percentage, can significantly affect the flow, much more than an equal percentage change in the tube’s length.
- Flow restriction can also be adjusted through the tube’s length. Longer tubes reduce flow by increasing restriction, but excessively long tubes can be inefficient and uneconomical.
- Critical Flow Dynamics:
- Shorter tubes increase flow gradually until a critical point is reached. Beyond this point, further reductions in length cause more rapid increases in flow.
- Once the tube is very short, small changes in length can produce large flow increases, and the tube begins to behave more like an orifice than a capillary.
- Optimal Length Range:
- For optimal performance, maintain the tube length within a range of 5 to 16 feet (approximately 1.5 to 4.9 meters).
- Although there are exceptions, staying within this range generally ensures efficient daily operation of window air conditioners.
By following these guidelines, you can achieve reliable and efficient operation of your air conditioning system equipped with R410A refrigerant.
