DHW Coils and De-liming?

So last night while laying in bed my mind starts to wander. I started thinking "Is there so maintenance I should be doing on the coil?".
So any advice out there?
I await your replies so I can have a better night's sleep!

I've never done it. The inside seems pretty clean each spring when I remove them.

The outside is a completely different story though. They get the twisted-wire wheel treatment - makes short work of the buildup.

These aren't DHW coils though ...

Usually nothing is done until they do not supply the hot water needed. Then a bunch of valves & an acid pump, pumping reverse to the normal flow of water...until it flows easily or 5 minutes, which ever comes first. It's smelly, somewhat dangerous & you have to have an acid pump. Acid used to be $19 a gallon. I bought a gallon last year & it was $45!!!!

PS While I was doing that sort of thing on a regular basis, we never burned through a coil (watch those 5 minutes) ....but it can and does happen, so there's always the possibility you immediately need a new coil.

I'd give the coil a nice flush in both directions once per year just to keep sediment to a minimum...other than that, if it is working fine stay away from the acid.

Makers of tankless water heaters recommend flushing their coils with white vinegar. It does a fair job and will not blow through the coil, and a few gallons at the grocery store is cheap.