Water Heater Repair
Troubleshoot cold showers, tank leaks, rumbling and pilot or heating element faults.
Homeowner guide
Water Heater Leaking From the Bottom? Tempe, AZ Guide
Water on the floor under a tank is not always the tank. Check the connections, the relief valve and the drain valve first, then work out if the unit needs a repair or a replacement.
By the Tempe Express Plumbing team ·
Shut things off first
Turn off the power at the breaker, or set a gas heater to pilot or off. Close the cold water valve above the tank. This stops the tank refilling and the leak growing.
Avoid draining a leaking tank through the hot taps unless you are prepared for scalding water. Lift stored items off the floor and take photos of the leak.
Finding the source
Inspect the cold inlet and hot outlet at the top, the pressure relief valve on the side and the drain valve near the base. Water from any of them can trickle down the tank to the floor.
Dry each part with a towel and watch which one gets wet first. A loose fitting or a failing valve is a repair.
When it is the tank itself
If water seeps from the tank body, the base or the seam, the steel lining has failed. That cannot be patched. Rust streaks and a damp jacket are the usual signs.
A tank that has reached this point needs replacement. See water heater replacement for the choices.
Finding the source
Where it leaks decides the repair.
| Source | Typical sign | Usual fix |
|---|---|---|
| Inlet or outlet fitting | Drips from the top connections | Tighten or replace |
| Relief valve | Water at the discharge pipe | Replace the valve, check pressure |
| Drain valve | Drip near the bottom | Replace the valve |
| Tank body | Seepage from the shell, rust streaks | Replace the heater |
Condensation and false alarms
Gas heaters create some condensation on startup, and a cold tank in a warm garage can sweat. Wipe the area and see if water returns in an hour.
If the puddle returns with the heater off, the leak is real. Do not assume it is condensation until the floor stays dry.
Why heaters fail in the Valley
Minerals settle on the tank floor over the years. The city notes Salt River water carries more dissolved solids and Verde River water more hardness, so sediment accumulates. An annual flush slows the damage.
Heat does not harm the tank, but a tank in a hot garage can hide a leak until the floor is wet.
Relief valve leaks
A dripping relief valve suggests either excess pressure or a worn valve. Its discharge pipe must run to a safe spot, and the outlet must never be capped.
Persistent dripping from the valve calls for a plumber, since the cause may be a failed expansion setup or high house pressure.
Repair or replace
Repair is reasonable for a fitting, a valve or an element. Replacement is the answer for a failed tank, or a unit that is old and failing in several ways. Compare both prices.
See water heater repair for what a plumber checks. For tankless options, read about tankless service.
What to ask before agreeing
Ask what the quote includes: the unit, a new relief valve, a drain pan, haul-away and any permit. Ask how long the work takes and whether hot water returns that night.
If the heater flooded the garage, the drying is a separate job.
Protecting the floor while you wait
A slow leak can ruin a floor long before the heater fails completely. Place a shallow tray or pan under the tank if none is installed, and check that any existing drain pan is not clogged. Move boxes, tools and stored items off the floor, and keep cardboard away from the base, because it soaks up water and hides the damage.
In a garage or closet, a wet-dry vacuum clears standing water quickly. Dry the area afterward with a fan so the wall base and the subfloor do not stay damp.
Gas and electric units need different precautions
On an electric heater, switch off the breaker before you do anything near the tank. A heating element sitting in a dry tank can burn out, and wet wiring is a shock risk. On a gas heater, turn the gas control to the off or pilot position and leave the vent alone.
If you smell gas at any point, leave the building and call 911 or the gas utility from outside. A leak and a gas smell together are an emergency, and the plumbing call can wait until the supply is safe.
Questions worth asking about a replacement
If the tank body is leaking, replacement is the only fix. Ask the contractor about the size, the fuel type and whether the new unit fits the same space. Older installations sometimes need a new vent connection, a larger pan or an expansion tank to meet current rules, and those extras change the quote.
Ask who removes the old tank and who handles the permit. The water heater replacement page lists the factors that affect timing and cost. If the leak comes from a fitting rather than the tank, water heater repair may be enough.
Planning the timing of a replacement
A leaking tank rarely gets better on its own. If the leak is small and the heater is old, plan for replacement soon, ideally before it fails during a busy week. A planned swap lets you compare quotes, choose the size and schedule a daytime visit.
An emergency swap is still possible, and the dispatcher can ask about same-day help, but options may be limited to what a contractor has in stock. If you can wait a day or two with the supply and power off, you may have more choices. Be sure everyone knows the heater is off.
A note on warranties
Check the label on the tank for the model and serial number, then look up the manufacturer's coverage. Many tanks carry a limited warranty on the shell for several years, but terms vary and often exclude labor. Photographs of the leak and the label help if you file a claim.
Short answers
Leaking heater FAQ
A fitting or valve leak can often be fixed. A leak through the tank body means the unit has to be replaced.
Yes. Shut off power or gas and the cold supply, then call.
Not long. A leak can grow into a flood. Shut it off and call.
Same-day visits are available for many swaps. Ask about unit availability on the call.
Services that fit this problem
Water Heater Installation & Replacement
Remove the dead tank and set a new heater matched to household size, fuel supply and available space.
Tankless Water Heater Service
Clear mineral scale from an on-demand heater, chase down fault codes, or install a new one.
Keep reading
Closing the main water valve
Locate and test your shutoff before an emergency. This guide covers finding it, closing it and what to do afterward.
Banging water pipes
A thud when a faucet or appliance valve shuts is water hammer. Learn the causes and inexpensive remedies.
Weak water pressure
One weak faucet and a weak house have different explanations. Check them in this order before booking a visit.
Sources
Figures and statements on this page that come from outside references are listed here.
Heater leaking now?
Shut off power and the cold supply, then call the 24/7 line. A dispatcher lines up a local contractor.