The cooling capacity of a 1/4 HP compressor in BTU depends primarily on the type of refrigerant used in the system and the operating conditions, such as the low pressure or the working temperature of the evaporator coil.
1/4 HP to BTU Conversion
The table below shows the approximate cooling capacity of a 1/4 HP compressor with R134a, based on the evaporation temperature:
| Evaporation Temperature (°C) | -35°C | -30°C | -25°C | -20°C | -15°C | -10°C |
|---|---|---|---|---|---|---|
| Capacity (BTU/h) | 366.64 | 519.54 | 709.33 | 940.93 | 1219.30 | 1549.36 |
Table: Average cooling capacity of a 1/4 HP compressor with R134a gas vs. evaporator temperature.
Example Calculation
From the table, we can see that a 1/4 HP compressor working at a temperature of -10°C with R134a gas achieves a cooling capacity close to 1549.36 BTU/hour.
Factors that Affect Cooling Capacity
It is important to understand that the refrigeration capacity may vary when the operating conditions change, such as:
- Compression process and compressor performance:
- A less efficient compressor will reduce cooling capacity.
- Frequency or motor speed (Hz or RPM):
- Changes in frequency affect speed and thus compressor performance.
- External temperature of the condenser area:
- Higher external temperatures can reduce system efficiency.
- Cooling method of the condenser coil:
- Natural or forced convection cooling affects the level of subcooling.
- Degree of subcooling of the refrigerant in the condenser:
- Better subcooling levels increase cooling capacity.
- Degree of superheating of the refrigerant at the evaporator outlet:
- Superheating levels affect the thermal performance of the system.
References Used for the Table
- Refrigerant superheating: 5°C (at the evaporator outlet).
- Refrigerant subcooling: 5°C (at the condenser outlet).
- Ambient temperature: 35°C.
Note: If any of these references change, the cooling capacity of the 1/4 HP compressor will also change.
