Water heater decision guides

Work through it in this order. First: is the tank itself leaking? If yes, the decision is made — a rusted-through tank has no repair. Second: how old is it? Read the date code on the data plate. Past about 12 years on a tank, most repairs are money spent on a unit that will fail again soon. Third: what failed? A thermocouple or heating element on a six-year-old unit is a clear repair.

Only once you have decided you are replacing does the type question become live. And the honest framing is: the default is like-for-like. Same fuel, same category, correctly sized. That is the cheapest, fastest, lowest-risk option, and for many households it is the right one.

Deviate from like-for-like when there is a specific reason. You genuinely run out of hot water today (size up, or consider tankless). You need the floor space. You are on electricity and want the lowest running cost (heat pump — ENERGY STAR requires UEF 3.30 or higher for certified integrated units). You are already opening up venting for other work.

Then apply the ownership test. Tankless has an ENERGY STAR life expectancy of about 20 years and saves roughly $95 a year against a standard gas storage model. Against conversion costs NerdWallet puts at $150-$2,500 on top of a $1,400-$3,900 install, the payback can easily exceed a decade. If you might move in five years, that math does not close.

How to choose

Read the date code first

It is on the manufacturer's data plate. Age is the single most useful input into repair-versus-replace and it costs nothing to find.

Distinguish tank leaks from fitting leaks

This one distinction changes the entire decision. Have the contractor point to the source.

Default to like-for-like unless you have a named reason

"The salesperson said tankless is better" is not a reason. "We run out of hot water every morning" is.

Apply the years-in-house test to any efficiency upgrade

If your payback is 11 years and you plan to move in four, the upgrade is a gift to the next owner. Sometimes worth it for resale, usually not.

Do not decide during an emergency if you can avoid it

Shut off the water, take a day, get two more quotes. Emergency decisions are where the expensive mistakes get made.