Sorry but filters only remove most of the sediment and softeners replace most of the calcium and magnesium with salt. Any water heater tankless or on demand, gas or electric should be flushed periodically if you want it to last longer. Prove it to yourself: get a pot of water from your tap, now boil it for a while, 1/2 hour maybe. Empty pot, do you see that white residue? That’s a hint as to what’s going on inside your water heating unit. You can further test by not cleaning pot and boiling more water and watch the residue build.

We had TECO install an exterior mounted tankless unit 18 months ago and it works great! No more delays than the old one in getting hot water to the far side of the house. With frequent visitors (4), we never run out. Highly recommend,

Thank you for all the post.
Now who would you recommend to purchase a new gas hot water tank unit? Would like excellent quality.

Call Mike Scott Plumbing. Reliable service, as good a price as you will get anywhere else, and no hassle.

Replace gas water heater
 

Approximately 6 years ago, I used TECO to replace my water heater. Excellent price built in to my monthly bill, fast courteous service, clean up including removal and no problems with new heater.