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Rust on Your Water Heater: Here’s What It Means

rust on old water heater tank

If you've ever seen rust on your water heater, you may be wondering if it means the end is near for your equipment. Below, we'll explore what rust can mean for your water heater and whether or not the equipment needs to be replaced. We'll also look at some of the most common causes of water heater corrosion. So, if you're seeing reddish-brown water or rust on your water heater, read on for more information!

Rust on Your Water Heater's Tank

If you see rust on the outside of your water heater's tank, it's likely that the metal has begun to corrode. This can happen for a number of reasons, but the most common is that the water heater's anode rod has failed. The anode rod is a piece of metal that's inserted into the water heater's tank to help prevent corrosion. Over time, the anode rod will corrode in order to protect the tank. When this happens, the metal of the tank is exposed and can begin to corrode as well.

Even with an anode rod in place, hard water, or water with high mineral content, can also cause corrosion. If you have hard water and don't flush your tank regularly, the mineral buildup can accelerate the corrosion process.

So now you might be wondering: what makes a rusty water heater such a big problem? Unfortunately, a rusty water heater tank is brittle and becomes increasingly prone to leaks as the tank expands and contracts with temperature changes. If your tank has started to rust through, it's time to replace the water heater.

Rust on Top of Your Water Heater Tank

If you spot rust forming on top of your water heater's storage tank, there is most likely a leaky connection between your water heater and the water supply pipe. When this happens, leaking water can drip down onto your tank and cause it to rust. Contact a technician to see if they can help you repair the leak as well as control the corrosion that has started.

Rust in Hot Water or Reddish-Brown Hot Water

If rusty or reddish-brown water is coming out of your faucets when you turn on the hot water, it's likely that your water heater is corroding from the inside. A layer of glass lines water heater tank interiors, but age and sediment can wear through this layer to the tank's metal walls. The metal can corrode over time, especially if the water in your area is high in minerals.

If you've just started noticing the problem, you may be able to fix it by replacing your water heater's sacrificial anode rod. However, if your water heater is approaching its expected lifespan (8-10 years), the corrosion has most likely become an unavoidable problem. You will most likely need to replace the entire water heater.

Rust on the Water Heater's Pressure Relief Valve

The pressure relief valve is a safety feature that's designed to release water and pressure if the temperature or pressure gets too high inside your water heater. If you see rust around the valve, it often indicates that there is corrosion or mineral buildup inside the tank. It can serve as a warning sign that you may need to replace your water heater soon.

Rust on the Water Heater's Heat Exchanger

The heat exchanger is a coil of metal pipes that transfers heat from the burner to the water in the tank. The heat exchanger can rust over time as it comes into contact with water vapor in the combustion gases.

The good news is that there's no need to replace the entire water heater in this instance. If the heat exchanger has rusted, a technician can replace it. Just be sure not to delay the part replacement because a brittle, cracked heat exchanger can allow toxic combustion gases to escape.

Milford Water Heater Services

If your water heater is starting to show signs of rust, it's important to take action right away. Tri-City Heating and Cooling is ready to help! Contact our Milford plumbers today at (203) 303-5700 for assistance with all your water heater needs!