Yes, water tanks can explode, as the simple answer suggests. If you set the temperature too high or if your water heater’s pressure relief valve fails, your water tank could explode. It can occur with a gas or electric water heater. A pressure relief valve can fail if there is a blockage in the pipe or if the pressure cannot be released in any other way. If you suspect that your water heater isn’t working properly, you should have a professional inspect it.