From the lab

Sizing Guides

Gallons, GPM and first-hour ratings matched to your household’s busiest hour, so the fourth shower never runs cold.

Where to start in Sizing Guides

Buying a storage tank? Start with the sizing worksheet, which works from your peak hour rather than your headcount. Going tankless? What size tankless water heater walks through flow times rise, and the tankless size chart puts the answers in a table.

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