A water heater can leak due to many reasons. There are more than half a dozen components and reasons responsible for a gas hot water heater leaking from top. You may not find this reassuring but a gas hot water heater leaking from the top is better than it leaking from the bottom or some other part. That is because all the causes can be remedied. You don’t have to opt for a new heater. If the leak is at the bottom, then chances are high you may have to replace the unit. But that doesn’t mean you should leave a gas hot water heater leaking from top unattended.
Locate Leak Source
You need to look for the exact source of the leak. Begin by turning off the power supply. Make sure the thermostat control of a gas water heater is turned to its off position. Look for the cold water inlet. Leave this valve on as you would have the water pouring in so you can easily identify the leak. An empty tank or one that is not getting water flowing in will have pressure fluctuations and the leak may stop on its own. Also, wipe the area around the heater clean and dry so you can figure out new leaks. It is possible that you will mistake old spilled or pooled water as fresh leaks. Don’t keep the cold water inlet turned on perpetually. As you find the leak or the exact source, turn it off so the damage is contained.
Damaged Water Inlet Valve
Now, one common cause of a gas hot water leaking from the top is a damaged water inlet valve. The inlet valve or the outlet pipe may have a leak. It could be normal wear and tear, damage or a faulty component to begin with. Check the valve and if it is the cause of the leak then have it replaced. It is also possible that the valve will be loose and would thus require tightening. Tighten the nut and if it still leaks then get a replacement.
A loose pipe may also be the cause of a gas hot water heater leaking from top. Check the outlet fittings and the water inlet. Any water leaking from here or at any of the connection points will require tightening of the pipe. Take a wrench and tighten all the connections. All these components tend to get corroded over time. If tightening doesn’t work, replace the components.
Malfunctioning Temperature and Pressure Valve
A very common cause of gas hot water heater leaking from the top is a malfunctioning or damaged temperature and pressure valve, also known as a temperature-pressure relief valve. You may have to replace it or check the heat and pressure inside the tank.