Tank Water HeaterLeak Repair2026-02-05
Water Heater T&P Valve Leaking Explained
A dripping temperature & pressure valve can be normal thermal expansion — or a sign of a real problem.
The T&P (temperature and pressure relief) valve is a critical safety device. A leak can be harmless thermal expansion or a warning sign.
Why it drips
Occasional drips can come from thermal expansion (especially on closed systems without an expansion tank). Frequent or steady discharge can mean excess pressure, too-high temperature, or a failing valve.
What to do
Don't plug or cap a discharging T&P valve — it's protecting you. Have the temperature setting, pressure, expansion tank and valve checked.
Key takeaways
- Never cap or block a T&P valve
- Frequent discharge needs investigation
- An expansion tank often fixes expansion drips
- Check temperature setting and pressure
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