If your water heater has developed a leak, you will need to check where the leak is coming from before you can try to fix it. You may have to replace the water heater altogether if it is an older heater. There aren't many causes of water heater leaks that can be fixed, but we will discuss how to fix the problems you can. Before you begin, you will need to have some tools handy. These include a screwdriver, some hose, a bucket, a wrench and some sealant. Once you have assembled all your tools, take a look at the water heater. If the water is leaking from the tank, you will need to replace the whole water heater. If the fittings or pipe is where the leak is located, you can probably fix it yourself. Now that you have assessed that the leak is not from the tank itself, you will need to prepare to fix the leak. First you will need to shut off your power.
If you have a gas water heater, then shut off the gas. This is a safety measure that needs to be followed. Do not attempt any repairs without doing this first step! Next you will need to shut off the water. You can easily do this by shutting off the in-line valves that are close to your heater. Then you will need to employ the sillcock valve at the bottom of the heater. Attach the hose and allow everything to drain either outside or down a drain. You do this to relieve any pressure that has built up inside the tank, and you will need to allow some time to pass before you proceed. Once the pressure has been relieved, disconnect your water intake and output by unscrewing the unions on the heater. Be sure you use your bucket to catch any remaining water that may leak out. Once all this has been done, you can use your wrench to tighten the fittings and valves. You may want to remove these items first and apply the sealant to the threads before tightening them back up. This should have fixed any of the leaks you had, and once everything is tightened up, you can then turn the water, power and heater back on. If this hasn't fixed your water heater leak, there are some other possibilities that may be causing the leak. If it is your temperature release valve that is leaking, you will need to call an experienced plumber to fix the problem. Doing this type of repair yourself if you do not know what you're doing can easily cause an explosion. Another option would be to tighten the drain valve.
Sometimes the drain valve loosens up a bit and causes a leak in the water heater. Lastly, check the heating element gasket. If this needs to be replaced, you will need to turn off the water supply and drain the water out of your water heater. You can then easily replace the gasket. Before you turn the water heater back on, you will need to run hot water through a kitchen sink to remove any air that may build up inside the heater tank