Yup, they stop your tank from rusting out. If you replace them regularly your tank will last virtually forever. If you don’t, you’ll be replacing the water tank before too long. A sacrificial anode costs around $50 bucks or so, a tank costs a lot more.
The phrase “sacrificial anode” comes to mind
That reminds me, I need to get a new one for my hot water tank. I’ve lived here 6 years, you’re supposed to change them around 5.
Wait, that’s a thing?
If it is, then my 10 yr old hot water heater isn’t happy.
Yup, they stop your tank from rusting out. If you replace them regularly your tank will last virtually forever. If you don’t, you’ll be replacing the water tank before too long. A sacrificial anode costs around $50 bucks or so, a tank costs a lot more.
Here’s a video showing you how to do it. It’s not very hard at all. https://www.thisoldhouse.com/heating-cooling-2/how-to-replace-an-anode-rod-on-a-water-heater
It can be the difference between a water heater lasting 7 years and lasting 30.