There is a difference between a water heater leaking and a hot water heater leaking. A water heater leaking can be due to many reasons, all of which will apply to a hot water heater leaking. But the latter will have one more potential cause, which will almost always be the case. If a water heater doesn’t leak in normal conditions, especially when it is not in use, then the same water heater leaking when it is hot or when you are using it for relatively high temperatures will mean there is only one problem.
Water heater is a reliable appliance and can function every day without any problem but it is an appliance and like all appliances, there can be some issues from time to time. A new water heater will have a warranty and the common problems are usually covered. An old water heater will not only be beyond warranty but it will also be vulnerable to many more problems. Let us explore why a water heater may leak.
Malfunctioning Drain Valve
The most common reason for leaks in a water heater is a malfunctioning drain valve. The drain valve may be loose, it may be improperly fitted in the water heater, it may have come loose due to use or it may have just worn off. The valve may be too tight, which is not really desirable as it leads to fissures and cracks. The drain valves are rather easy to deal with. You should check them and see if they are tight enough. If not, then you should just tighten them a little. Make sure you don’t tighten them too much. If the drain valves are very old, have them replaced. General wear and tear, corrosion and rusting can cause also leaks.
The second most common reason cause for a water heater leaking is excessive pressure inside the unit. All water heaters have a certain capacity. It can only heat so much water in a certain period of time. This is primarily significant because the appliance is designed to withstand the pressure of the water and the temperature of the heated water. If you set the thermostat setting too high, expecting very hot water, then you would be exerting phenomenal stress on the temperature-pressure relief valve. Not only would the water heater be unable to heat the water and deal with the expansion but the relief valve will malfunction as well. The temperature-pressure relief valve will cause the leak when the temperature or the pressure, mostly both happening in tandem, is too much to bear.
What Does This Mean?
The first cause is rather generic and can affect water heaters in an operational state and in a dormant or inactive state. The second cause is what’s responsible for hot water heater leaking. As the temperature inside the water heater rises, the water tends to expand. There is an increase in pressure due to the expanding water. The hot water can go on heating the water in the supply line but many homes prevent this endless dissipation of heat until the main supply inlet in the property. This causes an unnatural heating up of water in the heater and in the pipes. The extra temperature and pressure flag the temperature-pressure relief valve. The valve then allows water to leak to protect the heater. In some cases, the valve fails and that inadvertently leads to a leak.
Replace the Valves
Hot water heater leaking is common, especially in unmaintained water heaters and when the thermostat is set for an abnormally high temperature. There is a simple solution to this problem. You can reduce the thermostat setting. If you don’t, then you can consider replacing the valves. It is absolutely possible that the temperature-pressure relief valve is worn out or damaged. So even when you are using the optimal setting on the thermostat, you are having a leak because the valve is unable to do its job. You can reduce the temperature for now with such a heater but you should get the valve replaced. It will fail and you will have a leak regardless of the thermostat setting.
The other option is to go for an expansion tank. It is quite possible that you replace the temperature-pressure relief valve and yet it fails to prevent a leak because you need a certain degree of hotness for the water you use. You can get an expansion tank installed right next to the heater or anywhere in the property, as long as it is connected directly to the plumbing system and preferably close to the heater. The expansion tank will provide the space needed for the hot and expanding water to accumulate and this will reduce the onus on the temperature-pressure relief valve. If none of these remedies work for you, consult a plumber or your water heater company.