1. What is a 5 GPM Electric Tankless Water Heater Calculator?

Definition: This calculator determines the total flow rate needed for a small to medium household by summing the flow rates of individual fixtures.

Purpose: It helps homeowners and plumbers size an electric tankless water heater appropriately for a household's needs.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Total flow rate (gallons per minute)
• \( Q_i \) — Flow rate of each individual fixture

Explanation: The flow rates of all potential simultaneously used fixtures are added together to determine the required heater capacity.

3. Importance of Proper Sizing

Details: Correct sizing ensures adequate hot water supply while avoiding oversized units that waste energy and money.

4. Using the Calculator

Tips: Enter the flow rate for each fixture (default values are typical for standard fixtures). All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical flow rate for a shower?
A: Standard showerheads use about 2.5 GPM, while low-flow models may use 1.5-2.0 GPM.

Q2: Why size for 5 GPM?
A: 5 GPM covers most small to medium households with 1-2 bathrooms running 2-3 fixtures simultaneously.

Q3: What if my total exceeds 5 GPM?
A: Consider a larger unit or staggering hot water use. Electric tankless heaters typically max out at 5-8 GPM for residential use.

Q4: Does this include temperature rise?
A: No, this calculates flow rate only. Temperature rise depends on incoming water temperature and desired output temperature.

Q5: How do I find my fixture flow rates?
A: Check manufacturer specs or measure with a bucket and stopwatch (gallons collected divided by minutes).