The following table shows the BTU values for a 1/3 HP compressor:
| Temperature | BTU/h |
|---|---|
| -35°C | 388.47 |
| -30°C | 592.99 |
| -25°C | 830.55 |
| -20°C | 1108.75 |
| -15°C | 1435.18 |
| -10°C | 1817.44 |
Cooling capacity of a 1/3 HP compressor at different evaporation temperatures.
The average BTU value for a 1/3 HP compressor largely depends on factors such as the refrigerant type, the low-pressure value, or the working temperature of the evaporator coil.
For example, a 1/3 HP compressor operating at -20°C with R134a refrigerant achieves a cooling capacity of approximately 1108.75 BTU/h.
Factors Affecting Cooling Capacity
The cooling capacity of a 1/3 HP compressor may vary due to the following operating conditions:
- Compression process type.
- Compressor efficiency.
- Frequency (Hertz) variations.
- Compressor motor RPM.
- Ambient temperature around the condenser.
- Condenser cooling method (natural or forced).
- Degree of subcooling achieved in the condenser.
- Degree of superheating at the evaporator outlet.
- Refrigerant type.
Reference Conditions for the Table
The table assumes the following conditions:
- 5°C superheating at the evaporator outlet.
- 5°C subcooling at the condenser outlet.
- Ambient temperature of 35°C.
- Refrigerant gas: R134a.
If any of these reference conditions change, the cooling capacity of the 1/3 HP compressor will also differ.
Why Is It Important to Know the Cooling Capacity of a 1/3 HP Compressor?
Not all compressors with the same electrical power (HP) provide the same cooling capacity. When replacing a compressor with a different brand or model, it is crucial to select a compressor with the same cooling capacity, rather than focusing solely on the HP.
