Why does my hot water sometimes sound like popcorn?

Those descaler packets?

I’ve had the same “popcorn” noise in my tank a couple times, especially after skipping a year or two on flushing. I agree with you - descaler packets never seemed to do much for me either. I’m in a hard water zone too, and here’s what I do to keep things quiet (and hopefully extend the heater’s life):

1. Shut off power/gas and water supply.
2. Attach a hose to the drain valve, run it outside or to a floor drain.
3. Open the drain valve and let it run until clear.
4. Briefly open the cold supply to stir up remaining sediment, then drain again.

Takes maybe 30 minutes total if you’re set up for it. Not glamorous, but cheaper than replacing a burned-out element from all that buildup.

Yeah, the “popcorn” sound drove me nuts last winter. I tried those descaler packets once because a neighbor swore by them, but honestly, I couldn’t tell any difference. Flushing like you described worked way better for me. It’s wild how much gunk comes out, especially if it’s been a while. Sometimes I tap the side of the tank with a wrench while draining - seems to help loosen up stubborn stuff. Not sure if that’s official advice, but it hasn’t hurt anything yet...

Sometimes I tap the side of the tank with a wrench while draining - seems to help loosen up stubborn stuff. Not sure if that’s official advice, but it hasn’t hurt anything yet...

- Tapping the tank can actually help break up sediment, but just be careful not to go too hard - seen a few folks dent their tanks that way.
- I’ve found flushing twice in a row gets more out than any chemical packet ever did.
- The “popcorn” noise is classic trapped steam under sediment. If it’s really bad, sometimes you’ll see cloudy water for a bit after flushing.
- If you’re getting a ton of gunk every year, might be worth checking your anode rod too. Sometimes it’s just shot and letting more minerals build up.

Not sure I’d bother with tapping the tank, honestly. I’ve seen more people end up with a dent or chipped paint than actually getting more sediment out. Flushing a couple times back to back usually does the trick for me, and I’d rather not risk damaging the tank. The anode rod thing is spot on though - those get ignored way too often and can cause all sorts of issues down the road. If you’re getting that popcorn noise every year, it might be time to look at water quality or maybe even consider a softener... hard water can really do a number on these tanks.

I’ve run into that “popcorn” noise on a bunch of jobs, and honestly, it’s almost always heavy sediment buildup at the bottom of the tank. I get what you’re saying about tapping - people can get a little too aggressive and end up regretting it. I had a customer once who tried to DIY with a mallet and ended up with a leaky mess. Flushing a couple times like you said usually helps, but in areas with really hard water, sometimes you’re chasing your tail unless you address the water quality itself. Those anode rods are the unsung heroes - most folks don’t even know they exist until it’s too late.