Smell gas near a gas water heater?
Leave the building right away. Don't use light switches, phones or anything that could spark while you're inside, and don't try to find or stop the leak.
From a safe place away from the smell, call 911 or your gas utility. Don't go back in until responders say it's safe. (Source: Piedmont Natural Gas; your gas utility may be different.)
1. Make it safe first
If water is pooling or spreading, go straight to steps 2 and 3. The order below follows the manufacturer's guidance.
- Check that it's really a leak. Drops on the outside can be condensation. On electric heaters it usually goes away as the water warms. On gas heaters it can appear when cold water enters or the burner fires after sitting idle, and it's typically temporary. Also check that the water isn't coming from something nearby, such as a furnace or AC drain line or a water softener.
- Turn off the power or gas, if you can do it safely. Don't step into standing water to reach the electric panel; if the panel area is wet, stay out and call for help. Electric heater: switch off its breaker. Gas heater: close the gas shut-off valve near the heater, but only if you're confident doing it.
- Close the cold-water supply. Use the shut-off valve on the cold-water line that feeds the heater. If you can't find it or it won't turn, close your home's main water valve.
- Find where the water is coming from. Use the diagram below. Knowing the spot helps whoever you call.
- Don't attempt repairs while it's connected. Never work on the heater while power and water are still on. If you're not sure, call a professional.
2. Where is it leaking?
Tap a spot on the tank to see what it often means. The drawing is an illustrative tank-type heater; layouts vary by model, and tankless heaters are different.
Top of the heater: pipe fittings
Water at the top often comes from loose pipe fittings or connections. Tightening them may fix it.
Don't overtighten. That can damage the fittings and make the leak worse. If you're unsure, let a plumber do it.
Source: A. O. Smith, “Why Is My Water Heater Leaking?”
Side of the tank: temperature and pressure relief valve
This valve can release water when the temperature or pressure inside the tank is too high. The manufacturer's advice is to find the cause, not just replace the valve.
Ask a plumber to check why the valve is releasing water.
Source: A. O. Smith, “Why Is My Water Heater Leaking?”
Drops on the outside: condensation
Moisture on or under the heater isn't always a leak. On electric heaters it usually clears as the heater warms up. On gas heaters it can form when cold water enters or the burner fires after sitting idle, and it's typically temporary.
If the water keeps coming once the heater is warm, treat it as a leak.
Source: A. O. Smith, “Why Is My Water Heater Leaking?”
Near the bottom: drain valve
If the drain valve isn't closing properly, replacing the valve is usually the best solution.
Source: A. O. Smith, “Why Is My Water Heater Leaking?”
Under the tank: the tank itself
Water from the base is often the first sign of a serious problem, such as a corroded tank. In that case replacement is usually more practical than repair.
Replacing a water heater may need a permit. See the permit offices below.
Source: A. O. Smith, “Why Is My Water Heater Leaking?”
Before you call: what to note
- Where the water is coming from (use the spots above), and whether it's a drip or a steady flow.
- Gas or electric, and the model and serial number from the label on the tank. The plumber or manufacturer can tell the heater's age from it.
- What you've already done: power or gas off, cold-water valve closed.
- If you may contact your home insurer, take photos or video of the damage before you clean up. The NAIC recommends documenting losses first.
3. When to call a plumber
- Water is coming from the bottom of the tank.
- The relief valve on the side keeps releasing water.
- You can't find, reach or turn the shut-off valves.
- Water is near outlets, cords or the electric panel. Stay out of the water.
- You're not comfortable doing any of the steps above.
What happens when you call our line
A short automated prompt asks for your ZIP code. If an independent provider serving your ZIP is available, your call is connected. Availability isn't guaranteed, especially after hours.
Our referral line is free to use. Plumbing work is not: the provider quotes the job.
Not sure what to say? Get call-ready in three taps: safety steps, a one-line summary for the call and the questions to ask.
4. What to ask before work starts
- Their SC license number. Look it up with the SC Department of Labor, Licensing and Regulation before work starts. See how to check a plumber's license.
- Proof of insurance. The FTC suggests considering only licensed and insured contractors.
- A written estimate. It should describe the work, the materials, the completion date and the price.
- More than one estimate, when it isn't an emergency. The FTC also advises not to automatically choose the lowest bid, and to ask why estimates differ.
- Whether a permit is needed, and who pulls it. Greenville County, for example, says mechanical permits are required for new equipment and change-outs on properties it permits. Cities set their own process.
- When you'll pay. Don't pay the full amount up front, and hold the final payment until the work is done and you're satisfied.
5. Permit offices in the Upstate
If your address is inside city limits, start with the city's office; otherwise start with the county's. The office can confirm what applies to your home.
| Area | Official office | Covers |
|---|---|---|
| Greenville County | County permits | Properties the county permits |
| City of Greenville | Building permit applications | Inside Greenville city limits |
| Spartanburg County | Building Codes | Properties the county permits |
| City of Spartanburg | Residential building | Inside Spartanburg city limits |
| Anderson County | Building Codes | Properties the county permits |
| City of Anderson | Building and Codes | Inside Anderson city limits |
| Pickens County | Building Codes | Properties the county permits |
Other towns (for example Greer, Mauldin, Easley or Clemson) may run their own permit offices. Ask the county office if you're not sure. Step by step: who issues plumbing permits in the Upstate.
Common questions
Is a leaking water heater dangerous?
It can be. Water near outlets, cords or the electric panel is a shock risk, so don't walk through standing water to reach the panel. A. O. Smith notes that even small leaks can cause water damage and mold. Treat a leak as urgent: make it safe first, then get it checked.
Can I keep using the water heater?
No. A. O. Smith advises against continuing to use a leaking water heater, wherever the leak is. Keep it off with the cold-water valve closed until it's checked. Water from the bottom of the tank is often the first sign of a corroded tank.
Should I drain the tank?
You don't have to. Tank water can scald, and parts can stay hot after the heater is turned off. If you want to drain it, follow your heater's manual and let the water cool first; otherwise leave it to the plumber.
Will the warranty cover it?
It may. Check the label and the owner's manual for the warranty terms, and ask the plumber whether a repair or replacement could be covered before work starts.
Sources
- Piedmont Natural Gas, Natural Gas Safety (checked October 22, 2026)
- A. O. Smith, Why Is My Water Heater Leaking? (checked October 21, 2026)
- Federal Trade Commission, How To Avoid a Home Improvement Scam (checked October 21, 2026)
- CDC, Protect yourself from electrical hazards (checked October 22, 2026)
- NAIC, What you need to know when filing a homeowners claim (checked October 22, 2026)
- SC Department of Labor, Licensing and Regulation, Residential plumbing (last successful check October 22, 2026)
- Greenville County, Permits answer book (last successful check October 22, 2026)
- Pickens County, City of Greenville, Spartanburg County, City of Spartanburg, Anderson County and City of Anderson permit pages linked in the table above (last successful check October 22, 2026)