Quick Conversions
Conversion Formulas
L/s to CFM:
CFM = L/s × 2.11888
CFM to L/s:
L/s = CFM × 0.471947
Conversion Table: L/s to CFM
| Liters per Second (L/s) | Cubic Feet per Minute (CFM) |
|---|---|
| 1 | 2.119 |
| 2 | 4.238 |
| 3 | 6.357 |
| 4 | 8.476 |
| 5 | 10.594 |
| 10 | 21.189 |
| 15 | 31.783 |
| 20 | 42.378 |
| 25 | 52.972 |
| 30 | 63.566 |
| 40 | 84.755 |
| 50 | 105.944 |
| 75 | 158.916 |
| 100 | 211.888 |
| 150 | 317.832 |
| 200 | 423.776 |
Conversion Table: CFM to L/s
| Cubic Feet per Minute (CFM) | Liters per Second (L/s) |
|---|---|
| 1 | 0.472 |
| 5 | 2.360 |
| 10 | 4.719 |
| 15 | 7.079 |
| 20 | 9.439 |
| 25 | 11.799 |
| 50 | 23.597 |
| 75 | 35.396 |
| 100 | 47.195 |
| 150 | 70.792 |
| 200 | 94.390 |
| 250 | 117.987 |
| 300 | 141.584 |
| 500 | 235.974 |
| 1000 | 471.947 |
Step-by-Step Conversion Examples
Example 1: Converting 15 L/s to CFM
1 L/s = 2.11888 CFM
15 L/s × 2.11888 = 31.7832 CFM
Example 2: Converting 100 CFM to L/s
1 CFM = 0.471947 L/s
100 CFM × 0.471947 = 47.1947 L/s
Example 3: HVAC System Application
Related Flow Rate Conversions
L/s to Gallons per Minute
1 L/s = 15.850 GPM
Multiply L/s by 15.850323
L/s to Cubic Meters per Hour
1 L/s = 3.6 m³/h
Multiply L/s by 3.6
CFM to Cubic Meters per Hour
1 CFM = 1.699 m³/h
Multiply CFM by 1.699011
CFM to Gallons per Minute
1 CFM = 7.481 GPM
Multiply CFM by 7.48052
Common Applications
HVAC Systems
Air conditioning and heating systems use CFM measurements to determine airflow capacity and efficiency. Converting L/s to CFM helps engineers design proper ventilation for buildings.
Industrial Ventilation
Manufacturing facilities require precise airflow measurements for worker safety and equipment cooling. Flow rate conversions ensure compliance with safety standards.
Pump Specifications
Liquid pumps are rated in various units depending on region. Converting between L/s and CFM helps compare pump performance across different measurement systems.
Environmental Control
Clean rooms, laboratories, and controlled environments require accurate airflow measurements. Proper conversions ensure environmental parameters meet required specifications.
Popular Flow Rate Conversions
10 L/s = 21.19 CFM
Common residential HVAC capacity
50 L/s = 105.94 CFM
Small commercial system rating
100 L/s = 211.89 CFM
Medium commercial ventilation
500 CFM = 235.97 L/s
Large residential air handler
Frequently Asked Questions
What is the exact conversion factor from L/s to CFM?
The precise conversion factor is 2.11888. This means 1 liter per second equals 2.11888 cubic feet per minute. The factor derives from converting liters to cubic feet (0.0353147) and seconds to minutes (60).
Why do HVAC systems use different flow rate units?
Different regions adopted different measurement systems historically. North America primarily uses CFM (imperial units), while most other countries use L/s (metric units). Both measure the same physical quantity—volume flow rate—just in different units.
How accurate do flow rate conversions need to be for HVAC design?
For most HVAC applications, rounding to two decimal places is sufficient. However, critical applications like clean rooms or specialized industrial processes may require higher precision. Always consult relevant codes and standards for your specific application.
Can I use these conversions for liquid flow as well as air?
Yes, L/s and CFM are volumetric flow rate units applicable to any fluid, whether gas or liquid. The conversion factor remains the same regardless of the substance, as it only converts volume and time units.
What is the difference between CFM and SCFM?
CFM (Cubic Feet per Minute) measures actual flow at current conditions, while SCFM (Standard Cubic Feet per Minute) measures flow normalized to standard conditions (typically 68°F and 14.7 psia). SCFM accounts for temperature and pressure variations, making it more useful for comparing equipment across different conditions.
How do I measure flow rate in L/s or CFM?
Flow rate can be measured using various instruments including anemometers (for air), flow meters, pitot tubes, or orifice plates. The measurement device provides a reading that can then be converted between units as needed using the conversion factors provided.
What flow rate is typical for residential HVAC systems?
Residential HVAC systems typically range from 200-2000 CFM (94-944 L/s) depending on home size and climate. A general rule is approximately 400 CFM (189 L/s) per ton of cooling capacity, though this varies based on specific system design and local requirements.
Does altitude affect CFM measurements?
Yes, altitude affects air density, which impacts CFM measurements. At higher altitudes, air is less dense, so the same mass flow rate results in higher volumetric flow (CFM). For precise work at altitude, use SCFM (Standard CFM) which normalizes for pressure differences.