Should I Preemptively Replace My Old Water Heater?

2016 Feb 02
Posted in: Plumbing

Your water heater is old, and you know it. 

And now you’re faced with the question, “Should I preemptively replace my 10-year-old+ water heater, or should I just wait until it dies?”

On the one hand, you want to avoid the potential disaster that is 50 gallons of water flooding your home or garage. On the other hand, if ain’t broke why fix it, right?

Well, since traditional, tank-style water heaters typically last 6-10 years in the Phoenix area, you should, at the very least, start thinking about a getting new water heater now.  But you don’t necessarily need a new water heater.

But you absolutely HAVE to replace it when you see signs of tank corrosion.

What are signs of water heater tank corrosion? We’ll get to that. But first, let’s talk a bit about why a water heater tank corrodes in the first place...

Why water heater tanks corrode and leak

Most water heaters tanks are made of steel. Steel is made of iron. And when iron and water meet, rust (corrosion) happens. Even with a protective glass or enamel coating, a steel water heater’s tank will eventually rust.

That’s why your water heater has a sacrificial anode rod. This rod’s sole purpose is to slow down tank corrosion by rusting in place of the tank. In other words, it sacrifices itself to save your tank. 

However, once these rods become completely corroded, your tank will start rusting (unless you replace the anode rod). In the Phoenix area, these rods last 3-6 years (even less if you have a water softener).

Now that you know why water heaters rust, here are some telltale signs that yours is already corroding...

3 Signs of a corroded water heater tank

Rust-colored water
If the water in your home is rust or brown colored, it could be a result of rust forming on the inside of your water heater tank.

Old pipes can also cause this rust-colored water. If the rust-colored water only comes out of the hot tap, it’s likely your water heater. If it comes from both hot and cold, it could be your pipes.

Water around the water heater
A leak is a sure sign of a failing water heater tank. Take a close look around the bottom of the tank for water or wet spots. 

Water around the water heater can also be caused by the temperature and pressure (T&P) relief valve, the check valve towards the top or on top of the tank. So if you find water, try to see if you can find where it’s coming from. Or call a plumber to check it out. If the T&P valve is discharging water consistently that may mean that you are having a pressure buildup in the tank and that a thermal expansion tank or other means of releasing pressure in your plumbing system is necessary.

Rust on the outside of your tank
Even if you don’t find any water on the outside of your tank, you may find rust. And rust on the outside of your tank (especially near the bottom) is a sign of a leak and an indicator that your tank could be in imminent danger of bursting.

If your old water heater has one or more of these signs, consider having a plumber replace it before the tank bursts and causes serious water damage. 

But, let's say your tank seems to be in good condition and you want to keep it running until it fails. You can minimize water damage from leaks by following these 2 tips.

How to prevent water damage from a water heater leak

Even a water heater that seems fine now can spring a leak. You should have your water heater maintained—Have a professional plumber flush your water heater, check your anode rod and make sure your water heater is in tip-top shape.

Get pricing on a new water heater

Want to know what a new water heater would cost for your home? Schedule an onsite consultation.

And, while you’re at it, you may want to check out this article: Storage Tank vs. Tankless Water Heaters for Phoenix, Arizona.