Pressure buildup in a water heater is never something to be ignored. If not repaired, your water heater becomes a ticking time bomb that could explode. If you notice the signs of pressure buildup, it's vital that you shut down the water heater until you can schedule an inspection and repair.
Symptoms of Building Pressure
The most obvious sign of overly high water pressure is that the pressure relief valve, located at the top of the tank, is regularly leaking water. Keep in mind that a pipe often routes water down to the ground, so you may see the leak at ground level but if you trace the pipe it will attach to the top.
Another sign of building pressure is loud noises or rumbling from inside the tank. Overly high temperatures are a common cause of high pressure, and at higher temperatures, the water can begin to boil which causes that rumbling noise.
Causes of High Pressure
There are several causes of high pressure. Sometimes the issue is the water source. The pressure of water coming into the tank could be too high, for example. Minerals in the source water can also cause high pressure. These minerals precipitate out and coat the inside of the tank, which reduces tank capacity and increases the chances of overheating.
Other problems can be in the tank itself. Blocked or damaged outlet valves may cause the tank to drain more slowly than it fills, thus increasing pressure inside. Another common issue is a failed thermostat or malfunctioning heating element that causes a dangerous rise in water temperature.
Most issues that lead to elevated pressure are repairable. In the case of high water pressure, your technician needs to determine if it is high municipal pressure or just elevated pressure on the line feeding into the water heater. Then they will install a pressure regulating valve on either the main water line or on the line feeding your water heater.
Hard water buildup requires fully emptying and flushing the tank to remove the residue. If you have extremely hard water, your tech may advise installing a water softener. Otherwise, annual flushing should be sufficient.
Finally, thermostat and heating element issues are typically an easy fix. The faulty component only needs to be replaced so that the overheating is no longer a concern.
Contact a water heater repair service if you suspect pressure issues with your appliance.