1. What is the Water Flow Calculation Formula?

Definition: This calculator determines the water flow rate needed in heating or cooling systems based on heat transfer requirements.

Purpose: It helps HVAC engineers and technicians properly size piping and pumps for thermal systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( ṁ \) — Mass flow rate (pounds per hour)
• \( Q \) — Heat transfer rate (BTU per hour)
• \( c \) — Specific heat capacity (BTU per pound per °F)
• \( \Delta T \) — Temperature difference (°F)

Explanation: The heat transfer rate is divided by the product of specific heat and temperature difference to determine required flow.

3. Importance of Flow Rate Calculation

Details: Proper flow rate ensures efficient heat transfer, prevents system damage, and maintains desired temperatures.

4. Using the Calculator

Tips: Enter the heat transfer rate in BTU/h, specific heat (default 1.0 for water), and temperature difference. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the typical specific heat for water?
A: Water's specific heat is 1.0 BTU/lb·°F, but it varies slightly with temperature and additives.

Q2: How do I determine the temperature difference?
A: Subtract the return water temperature from the supply water temperature.

Q3: What if I'm using a fluid other than water?
A: Use the specific heat value for your particular fluid (e.g., glycol mixtures have lower values).

Q4: How do I convert lb/h to GPM?
A: Divide lb/h by 500 (for water at standard conditions).

Q5: Does this account for system efficiency?
A: No, you may need to adjust for pump efficiency and heat losses in piping.