1. What is the Hot Water Tank Size Calculation?

The hot water tank size calculation determines the appropriate storage capacity needed to meet peak demand while maintaining efficiency. It considers the maximum hourly demand and applies a factor to account for recovery rates and usage patterns.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( Peak\ Hour\ Demand \) — Maximum gallons used in one hour
• \( Factor \) — Multiplier (typically 0.6-0.8) accounting for recovery rate

Explanation: The factor compensates for the tank's ability to recover (reheat) water during periods of use.

3. Importance of Proper Tank Sizing

Details: Correct tank sizing ensures adequate hot water supply without excessive energy costs from maintaining too large a volume.

4. Using the Calculator

Tips: Enter peak hour demand in gallons and select an appropriate factor (default is 0.75). Typical factors range from 0.6 for electric heaters to 0.8 for high-efficiency gas heaters.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine peak hour demand?
A: Add up the water flow rates of all fixtures likely to be used simultaneously during your busiest hour.

Q2: What's a typical factor value?
A: Most residential systems use 0.7-0.75. Commercial systems may use lower factors (0.5-0.6) with larger tanks.

Q3: Does this account for tank type?
A: Indirectly through the factor. Higher recovery systems (like gas) can use higher factors than electric tanks.

Q4: Should I round up the tank size?
A: Yes, always round up to the nearest standard tank size available from manufacturers.

Q5: What about tankless systems?
A: This calculator is for storage tank systems only. Tankless systems require different calculations based on flow rate and temperature rise.