Water heater guides
A good water heater project runs in four steps: size it (first hour rating for a tank, GPM at your temperature rise for tankless), choose a type, vet the installer and confirm licensing and permits, then verify the work at handover. Skipping the sizing step is the most common and most expensive mistake.
Sizing. Write down your busiest hour of hot water use - showers, dishwasher, laundry, all of it. Then buy a storage unit whose first hour rating covers it, or a tankless unit whose GPM at your winter incoming temperature covers it. ENERGY STAR's certified gas storage units carry an FHR of at least 51 gallons and certified gas tankless units at least 2.8 GPM over a 67°F rise - use those as reference points, not as your answer.
Choosing a type. The default is like-for-like. Move away from it only for a named reason: you run out of hot water, you need the space, you want the lowest electric running cost (heat pump, UEF 3.30+ under ENERGY STAR criteria), or you are already redoing venting.
Vetting. Verify the license on your state licensing board's own lookup. Confirm insurance. Require an itemized quote with the specific model number. Ask who pulls the permit. Get three bids if you are not in an emergency - NerdWallet's 2026 ranges ($600-$2,500 tank, $1,400-$3,900 tankless) tell you when a bid is far outside normal.
Verifying. Permit number, inspection scheduled, warranty registered, no drips, T&P discharge properly terminated, shutoffs shown to you, temperature set deliberately. Then put the paperwork somewhere you will find it in eight years.
Choosing water heater an approach
The judgement calls that decide the bill, before anyone quotes you.
- Do the busiest-hour exercise before you shop Ten minutes with a pen prevents the two most common outcomes: an undersized unit you regret daily, and an oversized one you pay to keep hot for 12 years.
- Verify licensing at the source State licensing boards publish searchable lookups. A license number on a truck is not verification.
- Plan the replacement before the failure Past year 10 on a tank, start getting bids. A planned replacement costs less and lets you actually choose.
- Never DIY gas or venting Sizing, shopping, and even flushing an electric tank are reasonable homeowner activities. Combustion appliances are not.
- Keep every document Invoice, model and serial, permit, inspection report, warranty registration. All five get asked for eventually - at a claim, a service call, or a sale.
All water heater guides
Your Water Heater Is 10 Years Old
Tank vs Tankless Payback Math
Heat Pump Water Heater Rebates
No Hot Water Checklist
Water Heater Permits
Expansion Tanks and Tp Valves
Tankless Gas Line and Venting Costs
Water Heater Sizing Guide
Signs Your Water Heater Is Failing
Water Heater Brands Compared
Where these figures come from
Sources last checked
- ENERGY STAR - Residential Water Heaters Key Product Criteria · retrieved 2026-07-25
- NerdWallet - Water Heater Cost in 2026 · retrieved 2026-07-25
- U.S. Department of Energy - Home Upgrades · retrieved 2026-07-25
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