Techtanium indirect heater, Anode Rod replacement

[georgewny]

Looking for advice, am just a DIYer.
back in 2018, I had a plumber install a Techtanium indirect hot water heater.
Now fast forward to September 2024, and I just replaced both anode rods and did the first flush on the tank.
Can someone tell me if the picture of the rods look like normal erosion for a6 year old heater?

Also the color of the water from draining was a horrible rust color, see picture. This that normal for never having drained the tank in 6 years?

Thanks for any advice/information.

Regards
George

 

[breplum]

When anode rods are down to nothing, that indicates that they have sacrificed themselves as designed. Your old ones look to have a lot of life left. I have seen similar minimal sacrificial activity before.
Rusty water does indicate internal rusting is obviously occurring (unless you are getting dirty water coming in to the tank). So unless your unit is stainless steel then it is the glass lined steel tank. Steel tank linings can develop micro-cracks in the glass lining (though I thought that the lack of a burner would help with longevity. Those micro-cracks lead to rusting but, that is where the anode should be sacrificing…so maybe someone else knows why so much sediment.