A leaking water heater is more than an inconvenience — it’s a sign that something in your plumbing system isn’t working as it should. Even a small drip can lead to wasted water, higher utility bills, and costly damage to your flooring or walls. The sooner you understand why your water heater is leaking, the faster you can act to prevent a bigger problem.
At The Rooter Company, our professional plumbers have handled countless water heater leaks throughout the years. Below, we’ll explain the 7 most common causes of a leaking water heater and what you should do if you spot one in your home.
1. Faulty Drain Valve
The drain valve is located near the bottom of your water heater tank. It’s used to empty the tank for maintenance or replacement. Over time, the valve can become loose, worn out, or blocked by sediment buildup.
If you notice water pooling around the bottom of the tank, the drain valve might be the culprit. Tightening it slightly may stop the leak, but if the valve itself is cracked or damaged, it will need to be replaced. The Rooter Company’s plumbers can quickly inspect and swap out the faulty valve to ensure your system is watertight again.
2. Loose or Damaged Inlet and Outlet Connections
Your water heater has two key connections — one where cold water enters and another where hot water exits. These fittings can loosen over time as metal expands and contracts with temperature changes.
If you see water leaking from the top of the heater, it’s often due to these loose connections. Sometimes, tightening them solves the issue. However, if corrosion or rust is present, the fittings may need to be replaced entirely. A plumber can determine the exact source of the leak and secure your system safely.
3. Corroded Tank
Tank corrosion is one of the most serious and irreversible causes of a water heater leak. Minerals, sediment, and moisture buildup can cause the metal tank to rust from the inside out. Once corrosion weakens the tank, small cracks or holes can appear — and leaks will follow.
Unfortunately, once the tank begins to corrode, it cannot be repaired. In this case, replacement is the only long-term solution. The Rooter Company offers modern, energy-efficient water heaters that provide reliable hot water and peace of mind for years to come.
4. High Water Pressure
Water heaters are designed to handle a specific range of water pressure, typically between 40 and 60 psi. When your home’s water pressure is too high, it can stress your pipes, fittings, and the heater itself — eventually causing leaks.
A key sign of excessive pressure is water leaking from the temperature and pressure relief (T&P) valve. This valve is meant to release water when pressure gets too high, but if it’s happening frequently, your home’s pressure regulator might be failing. The Rooter Company can test your water pressure and install or adjust a regulator to prevent future damage.
5. Faulty Temperature and Pressure Relief Valve
The T&P valve plays an important safety role by preventing your water heater from exploding under extreme pressure or heat. However, if this valve becomes stuck, worn out, or installed incorrectly, it can cause water to leak continuously.
Sometimes, the leak can be fixed by cleaning or reseating the valve. But if the problem persists, it’s safer to replace it. The Rooter Company’s technicians can ensure your T&P valve is working properly and that your heater remains within safe operating limits.
6. Condensation or Excess Moisture
Not all “leaks” are actual leaks. When cold water fills a hot tank or when the air around your heater is humid, condensation can form on the outside of the tank. This is especially common in basements or garages with poor ventilation.
If the moisture appears as droplets rather than a steady drip, it’s likely just condensation. However, you should still keep an eye on it. If the moisture becomes more frequent or you notice standing water, it could be a sign of a hidden leak that needs professional attention.
7. Internal Tank Crack
Over the years, sediment buildup at the bottom of the tank can cause overheating. This repeated heating and cooling cycle expands the metal, eventually leading to internal cracks. These cracks are usually invisible from the outside but can cause constant leaking near the base of the tank.
Unfortunately, like corrosion, a cracked tank cannot be repaired. Replacement is the only safe and effective option. The Rooter Company can help you choose the right replacement unit for your home and ensure it’s installed correctly for long-term performance.
What to Do When You Notice a Leak
If you find water around your heater, act quickly to prevent damage:
- Turn off the power — switch off the breaker for electric units or turn the gas valve to “off” for gas heaters.
- Shut off the water supply — close the cold water valve leading to the heater to stop the flow.
- Call a licensed plumber — professionals can locate the leak safely and determine whether a repair or replacement is needed.
Never ignore even a small leak. What starts as a few drops can quickly lead to gallons of water flooding your home.
Preventing Future Leaks
Regular maintenance is the best defense against water heater leaks. Here are a few preventive steps:
- Flush the tank once or twice a year to remove sediment buildup.
- Check all valves, connections, and fittings regularly.
- Schedule annual professional inspections to catch early signs of wear.
- Consider installing a water softener if you live in an area with hard water.
At The Rooter Company, we provide full water heater maintenance services to keep your system in top shape. Our technicians inspect every component to ensure efficiency, safety, and longevity.
When It’s Time for a Replacement
Most traditional water heaters last between 8 and 12 years, depending on usage and maintenance. If yours is nearing that age and showing signs of rust, leaks, or reduced performance, replacement may be more cost-effective than constant repairs.
The Rooter Company offers fast, reliable installation of both traditional and tankless water heaters. Our experts can help you select an energy-efficient model that fits your household needs and budget.
Trust The Rooter Company for Water Heater Repairs
A leaking water heater is a problem you shouldn’t ignore — but it doesn’t have to turn into a disaster. With professional help from The Rooter Company, you can identify the cause, fix the issue, and restore your home’s comfort and safety.Whether you need a quick repair, routine maintenance, or a full replacement, our experienced plumbers are ready to help. Call The Rooter Company today for fast and reliable water heater service you can trust.