Water heater · triage
Water heater relief valve dripping or spraying
The short answer
The relief valve is a safety device that opens when the tank is too hot or the pressure too high. A steady flow of hot water: cut the energy and call today. A drip after use: book this week. Never cap or plug it.
Never plug the relief pipeBlocking the temperature and pressure relief valve removes the tank’s protection against overheating.
Know your shutoffs
Electrical panel and main breakerThe breaker panel (or fuse box), often in a garage, basement, utility room or hallway.Gas shutoffAt the gas meter outside (a valve on the pipe before the meter), and a smaller shutoff valve on the gas line next to each appliance.Main water shutoffWhere the water line enters the house: a basement or crawlspace wall, the garage, a utility closet, or near the water heater in warm climates.
Every outcome on this card
TodayThe relief valve is discharging
Cut the energy now; plumber today.
- Stay clear of the outlet The water can scald.
- Cut the energy Electric: breaker off. Gas: control knob to OFF.
- Close the cold-water valve and call a plumber Leave the relief pipe open.
A stuck thermostat or control can let the tank overheat; high street pressure or a failed valve can do the same. A plumber tests which.
This weekA small drip from the relief valve
Not urgent, but book it this week.
- Put a bucket under the pipe outlet Note how much collects in a day.
- Ask whether your home has a thermal expansion tank A plumber can check your water pressure.
- Book a plumber Worn valves and pressure problems are both common and fixable.
Drips after hot water use often point to thermal expansion with no expansion tank, or high incoming water pressure.
Related
Written from
Original casaq guidance, updated 2026-10-05. General guidance, not a diagnosis; licensed-pro review pending. Severity levels: Emergency now / Today / This week / This month / Watch. Send a correction.
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