Generator Size Calculator: What Size Generator Do I Need?
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Water heaters
How tank, tankless and heat pump water heaters compare on cost and efficiency, how cold winter tap water cuts a tankless unit’s flow, and what temperature to set a tank to.
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- Reviewed Oct 3, 2026
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Home Energy Guide
What Temperature Should a Water Heater Be Set At? 120°F, and When to Go Higher
Most homes should run a water heater at 120°F. What DOE, CDC, CPSC, EPA and OSHA each say, how fast hotter water burns, and what a lower setting really saves.
Home Energy Comparison
Tankless vs Tank Water Heater: Real Savings and Winter Flow Where You Live
Gas tankless beats a minimum-efficiency tank by $90–$210 a year but an ENERGY STAR tank by only $18–$42, and its flow drops with cold winter water. Estimates for 22 cities.
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