1. What is a Water Heater Size Calculator?

Definition: This calculator determines the appropriate size of a water heater based on water usage and recovery rate.

Purpose: It helps homeowners and plumbers select the right water heater capacity for optimal performance and energy efficiency.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Water heater size (gallons)
• \( U \) — Water usage (gallons)
• \( R \) — Recovery rate (gallons/hour)

Explanation: The water usage is divided by the recovery rate to determine the minimum tank size needed to meet demand.

3. Importance of Proper Water Heater Sizing

Details: Correct sizing ensures adequate hot water supply while maximizing energy efficiency and minimizing costs.

4. Using the Calculator

Tips: Enter your peak water usage in gallons and the heater's recovery rate (default 20 gal/h). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is recovery rate?
A: The amount of water the heater can heat from cold to the set temperature in one hour.

Q2: How do I estimate my water usage?
A: Calculate based on appliances and fixtures - showers (2.5 gpm), baths (30-50 gal), dishwashers (6-10 gal), etc.

Q3: What's a typical recovery rate?
A: Standard is 20-30 gal/h for electric, 40-50 gal/h for gas water heaters.

Q4: Should I round up the calculated size?
A: Yes, always round up to the nearest standard tank size (40, 50, 75 gal, etc.).

Q5: Does this work for tankless water heaters?
A: No, tankless units are sized based on flow rate and temperature rise requirements.