Crackling Noise near waterline after Megasteam 396 installed

Options
miner1
miner1 Posts: 3
in Strictly Steam

Its been awhile since I've reached out on this site, had to get new user name and passsword, got some good advice on this site in past so I'm reaching out again. Had my boiler replaced (hole above waterline blasting steam up vent pipe) last fall 2025, got a few quotes and was amazed at the variation in pricing. Went with a plumber who learned steam from his dad and seemed solid. Install of the Mega Steam 396 3 section went well on my single pipe system, main header piping replaced with drop header (old piping did not have drop header), piping pitched properly and installed per spec, new piping to domestic coil in boiler, wet returns not replaced. Never had any issues with water hammer or carryover with old boiler.

System ran fine at startup and for two months was quiet, It was skimmed on startup and several times over a month drawing of 2 gallons at a whack. Two months on it started to develop a popping/crackling sound, noise was resonating through domestic hot water pipes, using a sounding rod it appears the noise is loudest at the safety valve tapping, water level is at specification up 28-7/8" from bottom of jacketing, covering hot water coil. Gauge glass level occilates 1" when steaming. Noise only occurs when calling for heat and making steam, not when responding to aquastat.

I called the install plumber and he said keep skimming, talked to different plumber who does my cleanings he said drain and refill. So this fall I skimmed some more before cooling down and flushing out the boiler twice, water was black/brownish, on last drain and refill water was clearish. It continues to make noise. After a few heating cycles I opened skim port and fired it up black/brown water flowed form skim port. Maybe need more flushing or chem clean?

I called US boiler and made contact with a helpful customer service guy who said you may have to chemical clean it but they don't recommend using chemicals if skimming works. And that if I use chemicals they don't have a reccomendation, he said there are lots of of the shelf additives with who knows what in them.

I'm debating whether to continue flushing and skiming or add some chemicals, so what chemical to add? The old manual from the burham that I replaced suggested TSP .4 lbs and Caustic soda .4lbs for a boiler holding 14 gallons.

My questions for those who had the patience to read this

Am I on the right track with this being carryover caused by contaminated water, if so why did it only begin after several cycles after install?

Should I continue to skim and flush until water is clear?

Should I just chemical clean with TSP and Caustic Soda skim and then flush the crap out of it?

Comments

  • STEAM DOCTOR
    STEAM DOCTOR Posts: 2,680

    8-way for the win. Just make sure not to leave too much in when you are finished. The whole bunch in and fire it up. Once it starts steaming, let it sit for a while. At least 30 to 60 minutes. Fire it up every once in awhile for a few seconds, just to make sure that the water is still hot. Drain and fill a bunch of times. To get out the bad stuff and the excess chemicals. Fire it up and see what happens

  • EBEBRATT-Ed
    EBEBRATT-Ed Posts: 21,341

    Arm and Hammer Washing Soda. I used to use TSP and that is fine as well but Washing soda is ok. Use 1 lb of washing soda for every 50 gallons of boiler water so .306lbs of washing soda is needed for your boiler which holds 15.3 gallons.

    1. drain boiler below gauge glass and install a skim tapping with a valve. Pour washing soda mixed in a bucket of warm water into the boiler through the skim tapping.
    2. Fill boiler so you can see water level. Start the burner and let it run until the supply pipe is hot but not steaming. shut burner off and start skimming SLOWLY. Add feed water slowly ….you only want a stream of water the size of a pencil. Skim until the water looks clean. An hour should be plenty.
    3. Let boiler cool. Drain and refill twice to get rid of washing soda. Refill and run
  • miner1
    miner1 Posts: 3

    Thanks for the advice Ed and steam doctor, I haven't done the chemical flush yet, I saw the Gerry Gill video where he was rinsing a boiler with a wand. This is something I'm going to do before chem cleaning. Even after two full flushes, and over 20 gallons of skimming, I still get dirty water after steaming, I think there is alot of sediment in bottom of boiler that stays in boiler even after draining and refilling twice. Once it is steaming it mixes in, I fired it up with the skim port open (very briefly), the water surging out was nasty black/brown. I called the install plumber he is comming over to help rinse, I've got a wand set up that will run thru one of the two condesate returns on the bottom, there should be a push nipple there connecting to the other sections. I'll let you know how it goes. I'm hoping my wet returns, which are not capable of being rinsed or flushed easily, will not recontaminate the boiler water, it would have to get up and over the hartford loop, when I drain the hartford loop, after the boiler is drained, it is clear water.

  • EBEBRATT-Ed
    EBEBRATT-Ed Posts: 21,341

    @miner1

    Some when doing a new install put a ball valve on the Hartford loop and then below the ball valve a large drain valve on the Hartford loop. Then you start the boiler and shut off the ball valve and open the drain That keeps the water in the boiler and run the boiler to flush out the returns.

  • AdmiralYoda
    AdmiralYoda Posts: 817

    Sounds similar to my 41 year old Peerless boiler….back before Rectorseal 8-way. When I first moved into my house 17 years ago I was always flushing the boiler water, sometimes weekly to try and keep the water clean. It would muck up pretty quick.

    The lack of maintenance before I moved in probably made it worse and I was probably cleaning some junk out. But fresh water is bad and increases corrosion so I was probably making the problem worse. I didn't know that at the time.

    I started using 8 way and initially the water would get cloudy as the 8 way was cleaning some of the gunk out. Fast forward a bunch of years and my boiler water stay crystal clean with the 8 way in it.

    Even after sitting for the entire off season when I crack the boiler drain and the float type LWCO no junk comes out. Just clean violet tinted water.

    The 8-way adjusts the pH to a point where it stops corrosion. So no more rusty, gunky water. It will also dissolve scale and other deposits over time. It's good stuff!

    ethicalpaul
  • mattmia2
    mattmia2 Posts: 18,399

    the contaminants could cause it to prime(foam) instead of surge. lye probably isn't a great idea as treatment. it won't hurt the iron but could damage anything rubber or plastic.

  • miner1
    miner1 Posts: 3

    So after flushing and getting a crazy amount of casting sand and crud from bottom of boiler using a flushing wand and over 50 gallons of flush water hauled out of the basement and dumped outside the noise persists. Upon restart I isolated the noise to only when the boiler is steaming, it does not occur when the burner is on for the tankless coil. The noise is due to tankless coil but I don't know why? When its popping I draw domestic hot water and it goes away. So essentially when there is cold water running through the coil the noise goes away completely. I have a thermoflow V7-5 coil, in a single pipe Megasteam396. The noise did not occur when the coil was new, it started two months after install, when it was running with cruddy boiler water? What is going on here? Is there scale and contaminants on coil that are causing this problem? I'm at a loss here, I'm discouraged with plumber who installed this new unit, he has not been helpful.

Categories