A leaking hot water heater can be both an inconvenience and a hazard. Fortunately, most reasons for a leak only require a small repair. The following are the five most common reasons for a leak.
1. Failed Temperature Regulation
When the temperature inside a hot water heater gets too high, steam and pressure build up in the tank. This pressure is released through the top of the tank, through the pressure relief valve, and it is then routed through a pipe towards the ground. With this type of leak, there may be both water and steam leaking from the overflow pipe. The culprit can be a failed thermostat, a failed temperature regulator, or a failed pressure regulator. Fortunately, these issues can typically be repaired.
2. Loose Water Lines
You have a cold water line that feeds into the tank, and then a hot water line that exits the tank and goes on to service the various taps in your home. If the seal at either of these connections fails, you will get a leak. This leak may be small or large, depending on how loose the water lines have become. Replacing the seals where the water inlet and outlet valves are attached to the tank solves the problem.
3. Drain Valve Failure
The drain valve is at the bottom of the tank. Its main purpose is for draining out the tank in order to flush and clean it once a year. It can also be used to drain the tank for servicing. If this valve fails, quite a bit of water can leak out very quickly. You will also likely notice that you have no hot water at the taps or greatly reduced hot water. A drain valve can be replaced, so there is no need to replace the water heater just yet.
4. Rust and Corrosion
Rust and corrosion lead to holes and cracks in your water heater tank. The culprit is usually hard water deposits, which collect in the tank and speed the process of oxidation. Once a tank has rust or corrosion, it cannot be repaired so you will need to replace the hot water heater. You can prevent a tank from rusting by having it flushed out annually to remove the hard water deposits.
5. Supply Line Leaks
Sometimes the leak isn't from the heater itself, but from either the incoming cold water supply or the outgoing hot water supply. If you are finding standing water near the heater but not directly beneath it, check the supply lines for cracks or holes that could be causing the leaks. You can then replace the damaged line.
Contact a plumbing company in your area for more assistance.