Emergency Plumbing → Water Heater
Four leak points, four completely different answers. Three of them are repairs measured in parts and an hour of labor. One of them means the tank is finished.
A water heater leaking from a top connection or the drain valve is usually a small parts repair inside one labor hour. A water heater leaking from the bottom of the tank body is corroded through and can only be replaced. Everything on this page exists to tell those two apart.
With a water heater leaking, the stored water sits at 120F or hotter, and on a gas unit a failing heater can vent badly at the same time. Make it safe before you diagnose it.
Before you diagnose
The valve on the cold pipe entering the top of the tank. That stops the tank refilling as it empties through the leak.
Electric: switch off the dedicated breaker. Gas: turn the control knob to off. Do not touch the gas supply valve unless you smell gas and are leaving.
Stored water sits at 120F or hotter. Relief-valve discharge and drain-valve water can scald, so do not put a hand in the flow to find the source.
Shoot the wet area, the tank label with its age, and the leak point. Those three photographs answer half of what a plumber will ask on the phone.
Where is my water heater leaking from?
Top connections mean a loose or corroded fitting, usually repairable. A dripping temperature and pressure relief valve means excess pressure or a failed valve. A drain valve at the base is a cheap part. Water from the tank body itself means internal corrosion and replacement.
Water runs downhill and along surfaces, so where it pools tells you almost nothing about where it started. A puddle on the floor is equally consistent with all four sources.
Photograph the wet point and the rating plate showing the manufacture date. Age is half the repair-or-replace decision, and it is the first thing a plumber will ask.
Every ranking page lists the relief valve as a leak source. None of them explains what a dripping one actually means, and the difference matters because it is the only leak on the tank that is a symptom rather than a fault.
A temperature and pressure relief valve opens when the water exceeds its rated temperature or pressure. If it drips persistently, the usual cause is house pressure that is too high or a thermostat set too hot, not a broken valve.
Replacing the valve without fixing the pressure gets you a new valve that drips. A plumber should check static pressure and, where it is high, look at a pressure-reducing valve or an expansion tank rather than just swapping the part.
Never cap, plug or reroute the discharge pipe upward
The discharge pipe on a relief valve exists so that a tank cannot become a pressure vessel. Capping it, plugging it, or running it uphill so it cannot drain removes the only protection the tank has. If the pipe is dripping onto something you care about, move the something, or have the discharge routed correctly to a drain by a plumber.
Stored water is held at 120F or above, which is hot enough to scald in seconds. Do not put a hand into a discharge stream to trace a leak, and do not lean over a relief valve that is actively venting.
The gas risk sits alongside it and gets missed while attention is on the water. A gas water heater that is failing may also be back-drafting, which puts combustion products including carbon monoxide into the room rather than up the flue.
The CPSC treats a working carbon monoxide alarm as basic equipment wherever fuel-burning appliances are installed. If yours sounds, or if anyone in the house has an unexplained headache or nausea near the unit, leave the building and call 911 or your gas utility from outside.
Know the line
Is it safe to shower while the water heater is leaking?
A short shower is usually fine if the leak is a fitting drip and the area around the tank is dry and being watched. Do not shower if water is pooling under the tank body, if the relief valve is discharging, or if there is any gas smell in the room.
The reason is mechanical rather than cautious. Drawing hot water pulls cold water into the tank, which raises internal pressure at exactly the moment the tank is least able to take it.
If the tank body is leaking, treat every draw of hot water as a small gamble. Corroded liners fail progressively and then suddenly.
Manufacturers write most of the ranking content on this query, which makes their repair-or-replace advice difficult to weigh. The rule is simpler than their guides suggest.
Indicative US ranges. Always get a written quote.
| Job | Typical range | Notes |
|---|---|---|
| Emergency trip fee | $75–$500 | Charged to attend and diagnose |
| Labor, standard hours | $100–$200 / hr | Weekday business hours |
| Labor, after hours | up to $350 / hr | 1.5×–2× the base rate |
| Fitting or drain-valve repair | small parts cost + labor | Usually inside one labor hour |
| Water damage cleanup, if it flooded | $1,000–$2,000+ | Separate restoration trade |
Replacement unit prices vary too widely by capacity, fuel and efficiency for a single honest figure, so what is published here is the labor and call-out side. Ask any quote to separate unit, labor and disposal as three lines. The rest of the rate structure is in our breakdown of what an emergency plumber charges.
If water has already spread across flooring, the drying is a separate trade and a separate bill. Should the leak be running faster than the tank can be isolated, close the property main as well, and our guide to the main shut-off valve covers where to find it.
Emergency Services 24H is a referral service. We do not employ plumbers, we do not sell water heaters, and we have no stake in whether yours is repaired or replaced.
Your request routes by ZIP code to licensed, insured contractors covering your area, and they contact you directly to quote and schedule.
24/7 dispatch network
Tell us where the water heater is leaking from and give us your ZIP code. Licensed, insured plumbers covering your area will contact you directly. No obligation to hire.
Fire, a gas smell, or an injury? Leave the building and call 911 first, then your gas utility or power company. Use this form once you are safe.
Straight answers
The questions homeowners actually search for on this problem, answered in plain language.
Browse all guidesFor a small drip at a top fitting, yes for a short period while you watch it. If water is emerging from the bottom of the tank body, stop: that is internal corrosion and the failure is progressive, so every hour risks a full tank release. If you can smell gas near the unit, leave and call the utility.
Only if the leak is from the tank itself. Leaks at the inlet and outlet connections, the drain valve, or the temperature and pressure relief valve are component problems and normally repairable. Water appearing from beneath the tank body, or rust weeping from a seam, means the liner has corroded through.
Not overnight, and not unattended. Shut the cold water inlet, then switch off the breaker for an electric unit or turn a gas control knob to off. Stored water sits at 120F or hotter, and a gas unit that is leaking may also be venting badly, which is a carbon monoxide risk as well as a water one.
A tank-body leak is not something to plan around. Some run for days and some open up within hours, and there is no reliable way to tell which you have. If the unit is past about ten years old and leaking from the tank, treat replacement as the only option and plan for it immediately.
A short one, if the leak is a fitting drip and the area is dry and watched. Do not shower if water is pooling under the tank, if the relief valve is discharging, or if there is any gas smell. Running hot water pulls cold water in, which raises pressure in a tank that is already failing.
Because it is doing its job. A T&P valve opens when temperature or pressure exceeds its rating, so a persistent drip usually means house pressure is too high or the thermostat is set too hot, not that the valve is faulty. Never cap or plug the discharge pipe, which is the one action that makes it dangerous.
Checked . If a figure here no longer matches its source, that is a bug, so tell us and we will correct it.
24/7 dispatch network
Tell us what has failed and where you are. We route your request to licensed, insured contractors covering your ZIP code, and they contact you directly.
Fire, a gas smell, or an injury? Leave the building and call 911 first, then your gas utility or power company. Use this form once you are safe.