Water heaters

How to tell if a water heater needs to be replaced

Age, recurring repairs, and visible tank corrosion are the main signals that replacement makes more sense than continuing to repair an aging water heater.

Difficulty
Easy
Time
15–30 minutes to assess
DIY cost
$0
Pro cost
$1000–$3500

Symptoms

  • Unit is approaching or past its typical 8–12 year lifespan
  • Repairs have become more frequent
  • Rust-colored water or visible tank corrosion
  • Rumbling noise despite flushing, suggesting heavy internal sediment or wear

Likely causes

  • CommonTank has reached or exceeded typical service lifeMost tank water heaters last 8–12 years; the manufacture date is usually coded into the serial number.
  • CommonVisible rust or corrosion on the tank bodyOnce the tank itself is rusting, it's generally not repairable.
  • PossibleRepeated need for the same or different repairsA pattern of recurring issues often signals broader wear rather than one fixable fault.
  • PossibleRising energy bills tied to declining efficiencySediment and aging components make older units work harder for the same output.

What to do

  1. Find the manufacture date, often encoded in the first few digits of the serial number on the rating plate, and check it against your unit's expected lifespan.
  2. Inspect the tank exterior and base for rust, especially near seams and the bottom.
  3. Review how many repairs you've needed in the past couple of years and their combined cost.
  4. Compare the cost of another repair to the cost of a new unit, factoring in the age of the current one.
  5. Consider whether your household's hot water needs have changed enough to warrant a different size or type (like tankless) at replacement time.
  6. If you decide to replace proactively, doing so before a failure avoids the water damage risk of waiting for a full tank leak.

Tools and parts

  • None required for the assessment
Replacement tank or tankless water heaterSearch: “water heater replacement gas or electric”

When to call a pro

A plumber can give you a firm assessment of remaining life and recommend the right size and type of replacement for your household.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.