How to Use the CFM per Ton Calculator

A CFM per Ton Calculator helps determine the amount of air (in cubic feet per minute, or CFM) delivered per ton of cooling capacity in an HVAC system.

What It Does:

In HVAC design and diagnostics, understanding CFM per Ton is crucial. Too little airflow can cause poor performance or freezing coils, while too much can reduce dehumidification. This calculator quickly tells you how balanced your system is.

---

Steps to Use:

1. Enter the total airflow in CFM (e.g., from a duct traverse or system specification).
2. Enter the cooling system capacity in tons (e.g., 3 tons).
3. Click the “Calculate” button to get the CFM per Ton value.

A well-performing HVAC system typically targets 350–450 CFM per Ton, depending on the climate and equipment design.

---

Example:

If your system provides 1200 CFM of airflow for a 3-ton air conditioner:

nginxCopiarEditarCFM per Ton = 1200 / 3 = 400 CFM/Ton

This result indicates balanced airflow for most standard conditions.

---

CFM per Ton Calculator FAQ

Q1: What does “CFM per Ton” mean?
A: It's the amount of air (in cubic feet per minute) delivered for each ton of cooling capacity in an HVAC system. It helps measure airflow efficiency.

Q2: What’s a good CFM per Ton range?
A: Typically between 350–450 CFM per Ton. For humid climates, closer to 350 for better dehumidification; for dry climates, 400–450 may be acceptable.

Q3: Can I use this for heating systems?
A: This calculator is designed specifically for cooling systems (air conditioning), but airflow targets may be similar in heat pump mode.

Q4: What happens if the CFM per Ton is too low or too high?
A:

• Too low: Risk of coil freezing, reduced cooling, and high static pressure.
• Too high: Reduced dehumidification, noisy ductwork, inefficient cooling.

Q5: Where can I get accurate airflow (CFM) values?
A: You can measure with a flow hood, anemometer, or estimate based on system specs and fan speed settings.