Water Heater Expansion Tank: lifespan, maintenance and replacement

Typical lifespan: 5–10 years (about 8 years).

Maintenance schedule

• Check air pressure (should match water pressure) — Annually
• Inspect for leaks or corrosion — Every 6 months
• Tap tank to check for waterlogging — Annually

Signs it needs replacing

• Tank feels heavy (waterlogged)
• Pressure relief valve on water heater keeps opening
• Visible corrosion
• Water dripping from tank

Tips

A failed expansion tank can cause your water heater's pressure relief valve to discharge — check annually.