Tank Water HeaterLeak Repair2026-02-01
Water Heater Leaking from the Bottom: Tank Failure
Water pooling under the tank usually means internal corrosion — and time for replacement.
When a water heater leaks from the bottom, the cause is often a corroded tank that can't be repaired.
Why tanks leak from the bottom
Years of sediment and corrosion eventually breach the steel tank's glass lining and shell. Once the tank itself leaks, it can't be sealed and needs replacement.
Rule out other sources
Before assuming tank failure, check the drain valve at the bottom and condensation (common on gas units) — these are repairable, unlike a perforated tank.
Key takeaways
- Bottom leaks often mean the tank has failed
- Check the drain valve before assuming the worst
- Some 'leaks' are just condensation
- Shut off water and power/gas if leaking
Need help with your tank water heater?
Licensed, gas-certified technicians serving Greater Vancouver since 1999. CombiBoiler.ca — A division of ROMA Heating Ltd..
Frequently asked questions
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