Repair or Replace Your Water Heater? What a Year of Service Calls Shows

“Is it worth fixing, or am I buying a new one?” is the first question on nearly every water heater call, and it usually gets answered with a shrug and a rule of thumb.

We had a better option available, so we used it. We went back through every water heater call we invoiced since mid-January of this year and sorted them by what actually happened. Not what we quoted — what got done.

57 calls, and it was close to even

Here is the split:

That surprised a few people on our end too. The assumption going in was that most water heater calls end in a replacement, because those are the jobs you remember — they take all day and there's a truck involved. The repairs blur together.

But roughly half of the time, someone called about no hot water and we left with the existing unit still in the basement, working.

What the 28 non-replacements actually were

This is the part worth reading, because it's a much shorter list than most homeowners expect:

Look at that top row. Pilot assemblies, thermocouples and gas valves were the most common thing we found, and none of them are expensive parts. A thermocouple is a metal probe that sits in the pilot flame and tells the gas valve it's safe to keep the gas on. When it weakens, the pilot lights and then dies thirty seconds after you let go of the button. That is a repair, every time, on a tank of almost any age.

Now look at the “nothing wrong” row. Seven calls — a quarter of the non-replacements — where the water heater was fine. In a couple of those the complaint was a hot water dispenser at the sink, or a fixture bleeding cold into the hot side, or simply a long pipe run from the heater to a far bathroom. Two were inspections where we looked the unit over and told the homeowner it didn't need anything.

The one symptom that ends the discussion

If water is coming from the body of the tank itself, there is no repair. The tank is a steel cylinder with a glass lining and a sacrificial anode rod protecting it. Once the lining fails and the steel corrodes through, you cannot patch it, weld it, or seal it. Nobody can.

The catch is that water on the floor doesn't automatically mean the tank. Several other things drip and get blamed for it:

• The T&P relief valve discharging — often a pressure problem, not a tank problem.
• The drain valve at the bottom, which is plastic on a lot of units and weeps once it's been opened.
• The hot or cold connections up top, dripping down the side and pooling where you'd expect a tank leak.
• Condensate, on high-efficiency units, which produces real water for entirely normal reasons.

Three of our 28 repairs were venting or condensate issues, which is exactly this. Worth having someone confirm the source before you accept a replacement quote — we wrote up how to tell those apart in more detail.

Find the age before you decide anything

Age does more work in this decision than any other single fact, and it's printed on the unit. Look for the serial number on the data plate, usually on the front or side.

• Rheem and Ruud start the serial with four digits in month-then-year order. 0715 is July 2015.
• A.O. Smith and State generally lead with the two-digit year, followed by the week of manufacture.
• Bradford White uses a two-letter date code that needs a lookup chart — the letters aren't guessable.

A standard tank runs 8 to 12 years. Once you know where yours sits in that window, the decision gets much simpler:

The math we actually use

The rule we'd give a friend: if the repair costs more than about a third of a replacement, and the tank is past ten years, replace it.

An inexpensive part on a six-year-old tank is obvious — do the repair. An inexpensive part on a thirteen-year-old tank is the one people get wrong. It feels like the frugal choice, and sometimes it is: if the thermocouple buys you another year, that's a year you didn't spend anything real on. But if you're on your third repair in eighteen months, you've already spent replacement money in installments and still have a thirteen-year-old tank.

Count what you've spent on it in the last two years before you authorize the next repair. That number usually makes the decision on its own.

What each path costs here

We publish our rates, which is not standard in this trade and is a big part of why we wrote about plumber pricing in the first place.

Repair: a service call is $185/hour plus parts, Monday to Friday, 8am to 4pm. A thermocouple or thermostat is typically one visit.

Replacement: a standard 40 or 50 gallon gas or electric tank is $1,695 installed — unit, labor, haul-away of the old one and the permit. Gas and electric are the same price. A premium unit with a longer warranty runs $2,195, and tankless conversions are a different project entirely, covered in our tankless vs. tank cost breakdown.

There's currently $450 off any gas or electric tank replacement through the end of the year, which brings a standard install to $1,245. It has to be mentioned when you schedule. Tankless is excluded.

What we do on the call

There's no charge to hear what we think before we get there. Tell us three things on the phone — gas or electric, roughly how old, and what it's doing — and we can usually tell you which half of the 57 you're likely in before anyone gets in a truck.

On site, in order: age from the serial plate, find the actual water source if there's water, test the components that match the symptom, and drain some off the bottom to see what the sediment looks like. Then you get told what it is and what both options cost, and you pick. A $75 trip fee applies and covers the diagnostic visit.

If the answer is a replacement, the other thing worth knowing is that the new one lasts longer if it gets flushed — once a year is the whole program.

Common questions

Is it worth repairing a 10-year-old water heater?

It depends entirely on the part. A thermocouple or thermostat, yes — those are cheap and a ten-year-old tank may have years in it. A major component on a ten-year-old tank is a harder call. A leaking tank is not repairable at any age.

What's the most common water heater repair?

In our own records this year it was the pilot assembly, thermocouple and gas valve group — 6 of 28 repairs. Thermostats were next at 4.

How long should a water heater last in Portland?

8 to 12 years for a standard tank. Skipped flushing shortens it, annual flushing extends it. Tankless units commonly reach 20 with maintenance.

There's water under my tank. Is it definitely done?

Not definitely. Check the T&P valve, the drain valve and the top connections first. If the water is coming from the tank body itself, then yes.

Can I get a second opinion after someone told me to replace it?

Yes, and it's reasonable to want one. Seven of our 28 repair calls found nothing wrong with the water heater at all.