Identify whether water comes from piping, relief valve, drain, condensation or tank body. A leaking tank body is not fixed by tightening fittings. Follow the wet trail upward to the first wet point. Observe the discharge pipe from a safe distance and note when it flows.
What this covers
- Residential tank and heat-pump water heaters with visible leakage
What it does not cover
Differential
Likely causes of “Water heater is leaking or has water around the tank”, and how to tell them apart
- 1
A pipe fitting or a connection is dripping
What separates it Water appears at the top of the tank or at a pipe joint, and the drip stops when the water is turned off.
How to confirm Follow the wet trail upward to the first wet point.
- 2
The temperature and pressure relief valve is discharging
What separates it Water runs from the relief valve's discharge pipe, sometimes only when the heater is on, and the water pressure or temperature is high.
How to confirm Observe the discharge pipe from a safe distance and note when it flows.
- 3
Condensation is forming on the tank or pipes
What separates it Damp patches appear on a cold-water pipe or a tank in humid weather and dry in dry weather.
How to confirm Check whether the water returns only in humid weather.
- 4
The tank itself has failed
What separates it Water seeps from the tank body or the base and increases over time.
How to confirm A leaking tank body cannot be repaired; the tank needs replacing.
Before you touch a setting
Record this first — changing settings destroys the evidence
- Where the first wet point is and how quickly the water flows.
- Whether the heater was on, and the water pressure and temperature.
- The age of the tank and the state of the drain pan.
Try in this order
0 of 4 completedCapture the exact state
ReversibleTurn off the heat source as documented and locate the first wet point.
Separate the likely fault domains
ReversibleCheck nearby plumbing/condensation and observe relief discharge from a safe distance.
Correct only the proven, accessible condition
ReversibleUse a licensed plumber for relief-valve, gas, electrical, tank-body or concealed leakage.
Verify once before going farther
ReversibleRestore only after correction and safe refill/purge.
Stop boundary
When this stops being a self-service repair
- !Turn off the heat source as the manual documents, close the cold-water inlet and call a licensed plumber for relief valves, gas, electrical work or a leaking tank.
- !Do not tighten fittings on a leaking tank body; it will not stop the leak.
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Is a dripping relief valve dangerous?+
The valve is a safety device. A constant drip can mean high pressure or temperature, so have a plumber check it rather than capping it.
Why is the water heater leaking?+
Leaks come from fittings, the relief valve or the tank itself. A leaking tank cannot be repaired.
What should I do first?+
Turn off power or gas and the water supply and locate the source.
Is the relief valve the cause?+
A dripping valve suggests high pressure or temperature.
Should I call a professional?+
Yes. A leaking tank is a risk of damage.