About the Cooling Capacity Calculator
What is the Cooling Capacity Calculator?
This cooling capacity calculator measures how much heat an AC unit, AHU or chiller is actually removing. Use the air side (airflow and temperature drop across the coil) or the water side (chilled water flow and temperature rise).
It is useful for commissioning and checking whether equipment delivers its rated capacity.
How to use the Cooling Capacity Calculator
- Measured On (sample: Air side – airflow and temperature drop)
- Airflow (m³/h) (sample: 1,700)
- Water Flow (m³/h) (sample: 10)
- Temperature Difference (°C) (sample: 10)
- Press Calculate Cooling Capacity (results also refresh as you type). The result card shows the Cooling Capacity, along with In tons of refrigeration, In BTU/h and Note.
Formula used
Q = ṁ × cp × ΔT
- Air = Q (kW) = 1.2 × 1.005 × airflow (m³/s) × ΔT
- Water = Q (kW) = flow (kg/s) × 4.186 × ΔT
The air-side formula gives sensible cooling; moisture removal adds latent capacity.
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Measured On | Air side – airflow and temperature drop |
| Airflow (m³/h) | 1,700 |
| Water Flow (m³/h) | 10 |
| Temperature Difference (°C) | 10 |
| Result | Value |
|---|---|
| Cooling Capacity | 5.7 kW |
| In tons of refrigeration | 1.62 TR |
| In BTU/h | 19,432 BTU/h |
| Note | Sensible cooling only; dehumidification adds latent capacity |
Tips for using the Cooling Capacity Calculator
- Chillers are usually designed for a 5 °C rise across the evaporator (7 °C to 12 °C).
- 1,000 CFM is about 1,700 m³/h.