Why Is My Water Heater Leaking?

A leaking water heater may have a loose plumbing connection, a faulty valve, condensation or a deteriorated storage tank. Some causes can be repaired, while a tank that has corroded and begun leaking usually requires water-heater replacement.

Water near the appliance should be investigated promptly. Even a small leak can damage flooring, drywall, cabinets and nearby belongings. JeffCo Plumbers provides water-heater repair and water-heater replacement throughout Birmingham and Jefferson County, Alabama.

Call Roger Kelley at (256) 221-3387 if your water heater is leaking or has stopped operating correctly.

What to Do When Your Water Heater Is Leaking

If water is actively leaking from or around the appliance, take these steps when they can be performed safely:

Keep people away from the wet area. Water near electrical equipment can create a serious hazard.
Stop using hot water. Continued use can add water to the leaking system.
Shut off the water supply. Use the water-heater shutoff valve only if it is accessible and safe to operate.
Turn off the energy source. An electric water heater should be switched off at the appropriate breaker. A gas water heater requires special caution around its gas controls.
Call a plumber. The source should be identified before the water heater is returned to service.

Do not stand in water while touching electrical switches, breakers, appliances or wiring. If the area is unsafe or you are uncertain how to shut down the equipment, stay clear and request appropriate assistance.

If you smell gas, leave the building without operating electrical switches or creating a flame. Contact the gas utility or emergency services from a safe location.

First Determine Whether the Water Heater Is Actually Leaking

Water found beside a water heater does not always originate from the tank. It can travel from another plumbing fixture, pipe, drain, heating or cooling system, or foundation opening before collecting around the appliance.

Possible nearby sources include:

A leaking cold-water supply pipe
A leaking hot-water outlet connection
A nearby washing machine or utility sink
An air-conditioning condensate drain
A plumbing pipe above the water heater
Rainwater or groundwater entering the area
Condensation forming on cold pipes or equipment

The area should be examined carefully to determine where the water first appears. Drying visible water and observing where moisture returns may help distinguish an active water-heater leak from another nearby source.

Common Causes of a Leaking Water Heater

Loose or Leaking Water-Supply Connections

Cold water enters the heater through a supply connection, and heated water exits through another connection. Fittings, connectors and shutoff valves at the top or side of the unit can loosen, corrode or deteriorate.

A leak near the top of the appliance may run down the outside of the tank and collect at the bottom. This can make a connection leak appear to be a failed tank.

Faulty Temperature and Pressure Relief Valve

The temperature and pressure relief valve, commonly called the T&P valve, is a safety component designed to release water if temperature or pressure inside the tank becomes excessive.

Water may leak from the valve because the valve is defective, debris prevents it from closing, system pressure is too high or conditions inside the tank are causing it to open.

Do not cap, plug or obstruct the valve or its discharge pipe. Doing so can disable an important safety function.

Leaking Drain Valve

Storage water heaters usually have a drain valve near the bottom of the tank. The valve can leak if it is loose, damaged or no longer seals correctly.

Moisture around the drain valve may remain localized, or it may spread beneath the water heater and make the tank appear to be leaking.

Internal Tank Corrosion

A conventional storage water heater holds water inside a metal tank. Over time, corrosion can weaken the tank and create an opening that allows water to escape.

A leaking internal tank generally cannot be repaired as a normal plumbing patch. The water heater typically needs to be replaced.

Excessive Water Pressure

High plumbing-system pressure can place additional stress on the water heater, valves, connectors and other fixtures. It may contribute to leakage at fittings or cause the relief valve to discharge.

The cause of excessive pressure should be identified rather than repeatedly replacing the affected valve.

Thermal Expansion

Water expands as it is heated. In some plumbing systems, that expanding water cannot move backward through the supply system. The resulting pressure increase can stress the water heater and its safety components.

Diagnosing a thermal-expansion problem requires evaluating system pressure and the property’s plumbing configuration.

Heating-Element Seal Leak

An electric storage water heater contains one or more heating elements that pass through openings in the tank. A worn or damaged seal around an element may allow water to leak from the side of the unit.

Electrical power must be turned off before this area is examined or serviced.

Condensation

Condensation can sometimes form when cold water enters the tank or when nearby piping is exposed to warm, humid air. A small amount of condensation may be mistaken for a plumbing leak.

Persistent pooling, dripping or water that continues after the appliance has been operating normally should be investigated.

Tankless Water-Heater Connection or Component Leak

A tankless water heater does not store a large tank of hot water, but it can still leak from pipe connections, valves, seals or internal components. Condensation drainage may also be involved with certain installations.

JeffCo Plumbers provides tankless water-heater installation and evaluates qualifying tankless plumbing problems.

What the Location of the Leak May Indicate

Water Leaking From the Top

Water near the top of a storage water heater may originate from:

The cold-water inlet connection
The hot-water outlet connection
The shutoff valve
A connector or fitting
A pipe located above the appliance

Water can run down the exterior jacket, so the highest visible wet point is often more informative than where water collects on the floor.

Water Leaking From the Side

A side leak may be associated with a temperature and pressure relief valve, heating-element seal, fitting or internal tank problem. The exact configuration depends on the type and model of the water heater.

Water Leaking From the Bottom

Water beneath the unit may come from a drain valve, an internal tank failure or water traveling down from a connection above. Condensation or another nearby plumbing source can also create moisture under the appliance.

If water appears to be coming directly through the bottom of the tank, internal corrosion is a significant concern.

Water Coming From the Relief-Valve Discharge Pipe

Water from the relief-valve discharge pipe may indicate a defective valve, excessive pressure, excessive temperature or thermal expansion. The discharge should not be ignored or blocked.

Is a Leaking Water Heater Dangerous?

A leaking water heater can create several hazards depending on its location, energy source and the amount of water involved.

Water can contact electrical wiring or equipment
Hot water can cause burns
Wet flooring can create a slip hazard
Moisture can damage building materials
A malfunctioning gas appliance may create combustion or gas-supply concerns
A relief-valve problem may indicate abnormal temperature or pressure

Do not continue operating a water heater that is actively leaking until the source and condition of the equipment have been evaluated.

Can a Leaking Water Heater Be Repaired?

The answer depends on where the water originates.

A repair may be possible when the problem involves:

An accessible supply connection
A replaceable shutoff or drain valve
A relief valve that has failed
An electric heating-element seal
Another serviceable plumbing component

Water-heater replacement is commonly necessary when:

The internal storage tank is leaking
Corrosion has weakened the tank
The unit has several significant failures
Required repair is not appropriate for the equipment’s condition
The existing unit cannot safely return to service

The source of the leak should be confirmed before deciding between repair and replacement.

Why a Leaking Tank Usually Cannot Be Patched

The storage tank is an enclosed vessel that repeatedly heats, cools and holds pressurized water. A visible opening may be only one part of a larger area of internal corrosion.

A surface patch does not restore the structural condition of a deteriorated tank and may fail without warning. Replacing the leaking water heater is generally the appropriate response to an internal tank failure.

Why Is My Water Heater Relief Valve Leaking?

A temperature and pressure relief valve may drip or discharge because of:

A worn or defective valve
Debris preventing the valve from sealing
Excessive water-system pressure
Thermal expansion
Abnormally high water temperature

Replacing the valve without identifying the cause may not resolve the problem. If high pressure or temperature is responsible, the new valve may also discharge.

Never cap or plug the relief-valve outlet. Contact JeffCo Plumbers for a plumbing evaluation.

Why Is My Newer Water Heater Leaking?

A newer unit can leak because of a loose connection, damaged fitting, installation issue, defective component, excessive system pressure or another condition unrelated to the age of the tank.

Water may also come from an adjacent pipe or condensate line. The location and source should be confirmed before assuming the tank itself has failed.

Why Does My Water Heater Leak Only Sometimes?

An intermittent leak may appear only while the water is heating, after a large amount of hot water has been used or when plumbing-system pressure changes.

Possible causes include:

Thermal expansion during a heating cycle
A relief valve that opens under certain pressure conditions
Condensation during periods of heavy use
A fitting that leaks as temperatures change
A small tank opening that leaks more while the system is hot

An intermittent leak should still be evaluated. Temporary dryness does not necessarily mean the underlying condition has resolved.

Why Is the Water Heater Making Noise and Leaking?

Popping, rumbling or crackling sounds can be associated with sediment or mineral accumulation inside a storage water heater. A leak occurring at the same time may come from a valve, fitting or deteriorated tank.

The noise and leak may have separate causes, so the complete unit should be examined before deciding on a repair.

Why Is Rusty Water Coming From My Water Heater?

Discolored hot water may be associated with corrosion, sediment or another issue involving the hot-water system. If discoloration appears only when hot water is used, the water heater or hot-water piping may be involved.

If both hot and cold water are discolored, the source may be elsewhere in the plumbing or water supply. Avoid assuming that the water heater is the only possible cause.

How Plumbers Evaluate a Water-Heater Leak

A water-heater evaluation may include:

Confirming that the appliance is the source of the water
Checking visible hot- and cold-water connections
Examining valves and accessible fittings
Looking for evidence of tank corrosion
Determining whether water is coming from the relief system
Considering water pressure and thermal expansion
Evaluating the unit’s condition and installation

The findings help determine whether water-heater repair or replacement is the appropriate next step.

Water-Heater Repair or Replacement

Repair may be appropriate when the tank remains sound and the leak comes from a serviceable component. Replacement may be necessary when the tank itself leaks or the equipment can no longer operate safely and effectively.

JeffCo Plumbers provides the following water-heater services:

Frequently Asked Questions About Leaking Water Heaters

Should I turn off a leaking water heater?

Yes, when the shutoffs can be reached and operated safely. Stop the water supply and energy source appropriate for the appliance. Do not enter standing water to reach an electrical panel or control.

Can I continue using hot water if the leak is small?

Continued use can worsen the leak or create additional damage. The water heater should be evaluated before normal operation resumes.

Does water under the heater mean the tank has failed?

Not always. Water may come from a valve, fitting, pipe, condensation or another nearby source. An internal tank failure is one possibility, especially when water appears to come directly from the tank’s base.

Can a leaking water-heater tank be repaired?

A storage tank that has corroded and begun leaking generally requires replacement. Replacing an external valve, fitting or connection is different from attempting to patch a deteriorated tank.

Why is water dripping from the relief pipe?

The relief valve may be defective, or the plumbing system may have excessive pressure, thermal expansion or abnormal temperature. Do not block the discharge pipe.

Is condensation around a water heater normal?

Limited condensation can occur under certain conditions, but ongoing dripping or pooling should be investigated to rule out an active plumbing or tank leak.

Can a tankless water heater leak?

Yes. Tankless units can leak from pipe connections, valves, seals, internal components or condensate-related piping. The equipment should be evaluated to identify the source.

Is a leaking water heater an emergency?

A substantial active leak, hot-water discharge, water near electrical equipment, suspected gas leak or relief-valve malfunction requires prompt attention. Call JeffCo Plumbers for qualifying urgent plumbing service, subject to scheduling and availability.

Water-Heater Service Throughout Jefferson County

JeffCo Plumbers provides water-heater repair and replacement throughout Jefferson County, Alabama, including:

Call JeffCo Plumbers About a Leaking Water Heater

If your water heater is leaking, shut down the water and energy source when it is safe to do so and contact JeffCo Plumbers. Roger Kelley provides water-heater repair, installation and replacement throughout Birmingham and Jefferson County.

Call (256) 221-3387 or use the online contact page to request plumbing service.