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Water Heater Repair or Replace Calculator

Free tool

Repair it, or replace it?

You have a quote in your hand and no way to judge it. This runs the same three tests a good technician uses — the 50% rule, remaining life, and cost per year you'd actually get.

  • Straight verdict
  • Shows the break-even
  • Nothing to install
1What's broken

A storage tank water heater typically lasts 10 years.

9 yrs
$
$
2History
0

Minor parts are usually worth fixing on a unit with life left in it.

Our verdict
Replace it

At 9 years old, a repair buys you about 1 more year for $450 — that works out at $450 a year.

$450/yrrepair, per year
$150/yrreplace, per year
1 yrlife left if repaired
25%of replacement cost

Get this verdict in writing before you decide.

What this calculator does

It applies the three tests a good technician uses when deciding whether a repair is worth paying for — so you can judge a quote instead of guessing.

Test 1 — the 50% rule

repair cost ÷ replacement cost < 50%

If a repair costs more than half a new unit, you are spending most of the price of a replacement to keep something with a fraction of its life left. Some technicians tighten this to 40% once a unit is past halfway through its expected lifespan.

Test 2 — remaining life

Every appliance has an expected life: storage tank water heater 10 years, tankless 20, gas furnace 18, boiler 20, heat pump 15, fireplace 15, portable heater 8. Past about 75% of that, a repair is buying very little time.

Test 3 — cost per year

repair ÷ years gained vs replacement ÷ full life

This is the one people skip. A $450 repair that buys one more year costs $450 a year. A $1,800 replacement lasting 12 years costs $150 a year. Cheaper today is not cheaper overall.

When the answer is automatic

  • A leaking tank cannot be repaired — the steel has corroded through
  • Still under warranty? Check before paying; many tanks carry 6–12 year cover
  • Repeat failures in a short window usually signal the rest is going too

Worth knowing: planned replacement is cheaper than emergency replacement — you can shop around, and you avoid the water damage a failed tank causes.

3The three tests

Any single failure is a warning. Two or more and replacing is almost always the cheaper decision.

TestYour numberThresholdResult

Replacement costs are US national averages for a like-for-like swap. Get two written quotes before committing — prices vary widely by region and by how accessible the unit is.

Free checklist

Get your verdict plus the questions to ask your technician

We'll email the maths behind your result, along with the checklist that keeps a quote honest.

  • Your repair-vs-replace break-even in writing
  • 9 questions that expose an inflated quote
  • What a fair price looks like in your area

Send my breakdown to

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Common questions
What is the 50% rule?

If a repair costs more than half what a new unit would, replacing is normally the better buy — you are spending most of the price of a new appliance to keep an old one with a fraction of its life left. Some technicians use a stricter 40% threshold on anything past the halfway point of its expected lifespan.

My water heater is leaking. Can it be repaired?

If the leak is from a fitting, valve or connection, yes. If the tank itself is leaking, no — the steel has corroded through and no repair is possible or safe. A leaking tank always means replacement, whatever its age.

How long should each appliance last?

Storage tank water heater 10 years, tankless 20, gas furnace 18, boiler 20, heat pump 15, gas or electric fireplace 15, portable space heater 8. Hard water shortens a tank's life considerably; annual flushing extends it.

Is it worth repairing something still under warranty?

Almost always — check before you pay for anything. Many water heaters carry 6–12 year tank warranties and furnaces 10–20 years on the heat exchanger. Parts may be covered even when labour is not, which can cut a quote substantially.

The unit is old but working fine. Should I replace it early?

Planned replacement is usually cheaper than emergency replacement — you can shop around instead of accepting whoever is available on the day, and you avoid the water damage a failed tank can cause. Once a tank passes 10–12 years, budgeting for it beats being surprised by it.

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