1. What Is The Tankless Water Heater Sizing Calculator?

The Tankless Water Heater Sizing Calculator helps determine the appropriate size (in gallons per minute) of a tankless water heater needed for your household based on the total flow rate of all fixtures that may be used simultaneously.

2. How Does The Calculator Work?

The calculator uses the formula:

Where:

• \( GPM \) — Total gallons per minute required
• \( Fixture\_GPM \) — Flow rate of individual fixtures (gal/min)

Explanation: The equation sums the flow rates of all fixtures that might be used at the same time to determine the minimum GPM capacity needed for your tankless water heater.

3. Importance Of Proper Sizing

Details: Proper sizing ensures your tankless water heater can meet your household's hot water demands without running out of hot water during peak usage times.

4. Using The Calculator

Tips: Enter the flow rate of each fixture in gallons per minute. Add additional fixtures as needed. All values must be valid (GPM > 0).

5. Frequently Asked Questions (FAQ)

Q1: Why is proper sizing important for tankless water heaters?
A: Proper sizing ensures adequate hot water supply during peak usage and prevents overworking the unit.

Q2: What are typical fixture flow rates?
A: Shower: 2.0-2.5 GPM, Kitchen faucet: 1.5-2.2 GPM, Bathroom faucet: 0.5-1.5 GPM, Washing machine: 1.5-3.0 GPM.

Q3: Should I consider temperature rise when sizing?
A: Yes, temperature rise (difference between incoming water temp and desired output temp) affects the required unit size.

Q4: What if I have multiple bathrooms?
A: Calculate the total GPM of all fixtures that might be used simultaneously across all bathrooms.

Q5: Can I install multiple tankless units?
A: Yes, for larger homes with high demand, multiple units can be installed in parallel to meet hot water needs.