1. What is Mass Flow Rate in Refrigeration?

Definition: This calculator determines the mass flow rate of refrigerant in pounds per hour based on volumetric flow rate and refrigerant density.

Purpose: It helps HVAC technicians and engineers calculate refrigerant mass flow for system design, troubleshooting, and performance analysis.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( W \) — Mass flow rate (lb/hr)
• \( Q \) — Volumetric flow rate (gallons per minute)
• \( \rho_r \) — Refrigerant density (lb/gallon)
• 60 — Conversion factor (minutes to hours)

Explanation: The volumetric flow rate is converted to mass flow by multiplying by density and converting the time unit.

3. Importance of Mass Flow Rate Calculation

Details: Accurate mass flow rate is crucial for proper system sizing, charge verification, and troubleshooting refrigeration systems.

4. Using the Calculator

Tips: Enter the flow rate in GPM and refrigerant density (default 7.2 lb/gal for R-22 at 40°F). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why multiply by 60 in the formula?
A: This converts minutes (from GPM) to hours (for lb/hr) since there are 60 minutes in an hour.

Q2: Where do I find refrigerant density values?
A: Consult refrigerant property tables or manufacturer data sheets for specific refrigerants at operating conditions.

Q3: How does temperature affect the calculation?
A: Refrigerant density changes with temperature and pressure, so use values appropriate for your system conditions.

Q4: Can I use this for other fluids?
A: Yes, the formula works for any fluid when you know its density, though it's specifically designed for refrigerants.

Q5: What's a typical flow rate for residential AC?
A: Typically 3-6 GPM for residential systems, but varies by system size and design.