Question

In SI unit, one tone of refrigeration is equivalent to ______.

• A. 3.5 kW
• B. 4.5 kW
• C. 1 kW
• D. 2.5 kW

Hint:

Remember the standard conversion factor: \(1\text{ Ton of Refrigeration (TR)} \approx 3.5\text{ kW} \approx 50\text{ kcal/min} \approx 200\text{ BTU/min}\).

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
A Ton of Refrigeration (TR) is a traditional unit of power used to describe the heat-extraction capacity of refrigeration and air conditioning systems.
Key Formula or Approach:
One Ton of Refrigeration is defined as the heat transfer rate required to freeze 1 short ton (\(2000\text{ lbs}\) or \(907.18\text{ kg}\)) of pure water at \(0^{\circ}\text{C}\) into ice at \(0^{\circ}\text{C}\) within a 24-hour period.

Step 2: Detailed Explanation:
To convert this definition into SI units of power (Watts or Kilowatts):
- Latent heat of fusion of water \(\approx 333.55\text{ kJ/kg}\).
- Mass of 1 short ton \(\approx 907.18\text{ kg}\).
- Total heat extracted:
\[ \text{Total Heat} = 907.18\text{ kg} \times 333.55\text{ kJ/kg} \approx 302,590\text{ kJ} \] - Over a 24-hour duration (\(86,400\text{ seconds}\)), the rate of heat extraction is:
\[ \text{Power} = \frac{302,590\text{ kJ}}{86,400\text{ s}} \approx 3.517\text{ kW} \] - Rounding to one decimal place yields \(3.5\text{ kW}\).

Step 3: Final Answer:
In SI units, one ton of refrigeration is equivalent to approximately 3.5 kW.