There are multiple potential causes of water heater explosion, but most occur due to pressure problems. A broken temperature and pressure (T&P) relief valve, sediment buildup, or a bad anode rod are all dangers that can lead to an explosion. A gas leak can also cause an explosion, as it creates a major fire risk. While a T&P relief valve helps to regulate pressure, over time, the pressure can still wear down your tank. If the T&P valve starts leaking or frequently opens, you’ll likely have a pressure problem. If too much pressure builds up inside your water heater, it will eventually burst.