Tankless Water Heater Calculator
Calculate the perfect tankless water heater size for your home. Determine required flow rate, temperature rise, and energy needs for optimal performance and efficiency.
Step 1: Water Usage Specifications
5 GPM
Standard Flow Rates
Shower: 2.0-2.5 GPM. Faucet: 1.5-2.0 GPM. Dishwasher: 1.5 GPM. Washing Machine: 2.0 GPM. Calculate total simultaneous usage.
Step 2: Temperature Specifications
85%
Optimal Temperature Settings
Standard shower temperature: 105°F. Dishwasher: 120°F. Temperature rise depends on groundwater temperature and desired output.
Tankless Water Heater Results
Summary
System Visualization
Heater Comparison
Required Heater Size
36 kW
For 5 GPM at 70°F temperature rise
Total Flow Rate
5.0 GPM
Temperature Rise
70°F
BTU Requirement
122,850 BTU/h
Efficiency
85%
Water Heater System Visualization
Simultaneous Use
2 showers + faucet
Peak Demand
Moderate
Recovery Rate
Excellent
Energy Cost
$$ Medium
Tankless Heater Type Comparison
| Heater Type | Flow Rate (GPM) | Temperature Rise | Power/BTU |
|---|
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