Previously quiet and well working steam system now banging and spitting water - Solutions?

bdl

Just recently thought I should do some preventative maintenance on my Independence PV 6 gas fired boiler. Had some slow drain valves so thought it would be good to clear out some of the sludge. The boiler is 8 years old. It has a drop header design that I had downloaded from Burnham. After the initial shakedown (and fiddling with adjustments) it was provided decent and quiet heat. So called in a contractor to help out with this maintenance. Also asked for testing and adjustment (if necessary) for the gas burner.

The contractor did flush out water and cleared out the drains. Some of the drain valves were clogged with sludge. So he put in some liquid "stuff" to help with clearing out more of the crud. We had a discussion about this "stuff" and I said I've used Squick in the past, and it seemed to work for me. Anyways, the stuff is certainly doing something, since the water has gone from clear to muddy brown. He said to leave it in for a week and then he'll drain it out and refill the system.

There was a little noise in the pipes during heating but I thought it would quiet down. Towards evening - more like 6 hours after the contractor left, the heat came on and the hammer was awful. (The day before there was no such noise - it was a quiet system.) I turned off the boiler and waited for the water to drain back and it was nearly at the top of the sight glass, I estimate about 1.5-2" higher than NWL. Now some of this could be due to thermal expansion, but I've never seen that much water ever be quiet. So I drained the boiler down to NWL. I measured NWL from the bottom of the feet of the boiler to the water. (28-5/8") I put a marker line on the sight tube as a reference. This made it a little better the next firing, but the radiators sort of pant and you could hear water sloshing around. Sounds like a lot of water is being thrown up into the piping.

In the evening, I went to the upstairs bathroom and saw water on the floor. It had come from the radiator. This morning, the kitchen floor was wet - from the radiator there.

Pressuretrol is set to 1.5 psi Main, and about 0.75 psi differential. If you watch the safety gage, the boiler fires until 1.5psi. After it drops by 0.75psi, the fan comes on to get the burner ready to fire. Finally when the gage is at or below 0.5psi the gas is ignited. Isn't the idea to keep 0.5psi in the pipes to keep them hot? I have a 3psi gage, (from my previous boiler) but am struggling on how I can squeeze it in.

Sounds like really wet steam. Any suggestions?

I've lived in this house for 33 years, been through a couple boilers, and endured a few knuckleheads, but I'm not quite sure how to fix this one. Is this really just due to the "stuff" that was put in the water?

Do I need to clean out my Gorton valves now? (The ones that leaked cruddy water?)

ethicalpaul

The treatment is causing surging, as you thought it might be, which is causing water to get carried over and up into your main. After you drain it out and replace it with clean water you should be OK again. I wouldn't wait longer to drain it. It has probably done its job by now.

Keep an eye on the vents, but they're probably OK. You can rinse them out in vinegar or mild cleaner if they stick open

And it's OK if your pressure drops below .5 during the cutout. As long as it stays above 0 there's still steam in there. It's not to keep it hot, it's to keep steam in the pipes so they don't start drawing air back into the pipes before the boiler fires again

ethicalpaul

Here's what it looks like: https://www.youtube.com/watch?v=jvt8qxBaRJU

bdl

For draining, is this best done when warm or cold? (Obviously not hot or while firing!) Guessing while cold is safest, but may not clean the most gunk out.

BDR529

I know the gauges are working but did you take out the siphon loops and make sure they are clear? Also are you on a well?

bdl

BDR529 said:

I know the gauges are working but did you take out the siphon loops and make sure they are clear? Also are you on a well?

I haven't checked if the siphon loop is clear. Considering how much gunk was thrown around the system, it would be good to remove it and blow it out. Just have to unravel the puzzle to get it off. If I can do that, I will install my other low pressure gauge at the same time.

Not on a well. City water. Heavily chlorinated. Not sure of the pH.

Jamie Hall

If it ain't broke... as @ethicalpaul said, it's the stuff. You'll have to wait for the boiler to be reasonably cool, drain it all out, refill, and repeat. The bring the boiler up to steam to drive the air in the new water out.

And if it was running properly on city water before, it probably will again. Just don't mess with it. If you really feel compelled to "do something", try a little -- and I do mean a little, like a quarter or less of what it says -- Steamaster.

ethicalpaul

I drain mine at any temperature, but if your house is reasonably warm and you can wait for the water to cool a bit, the cooler the better. But it takes hours for the water and boiler to really cool.

Don't refill it really fast with cold water. I have no idea exactly how much of that a boiler can take without cracking, and I hope to never find out LOL. I refill at a rate of like a gallon every couple minutes or so.

You can overfill it before draining with some fresh water to cool it off also, which will let the water mix and bring down the temperature gently, but then that's more water you have to drain.

bdl

What initially compelled me to do this was the drain was blocked with mud. I had to use a thin wire through the valve into the boiler to get any water to run out. And then it only dribbled.
Thought it would be good to clean the boiler out. I'll let the house get warm tomorrow morning then shut the system off and wait for the water to cool down a bit. Might add a little fresh water, wait a bit, drain a little, add a little more fresh water, etc. until it's cooled down. Definitely not looking to crack a boiler!

As for not broken, the system worked ok. Not perfect, but not bad. Many years ago, I bought a couple of Dan's books, and worked out most of the problems in the system. There's still a few things to be fixed, but overall, it's pretty good. Had most of the vents balanced out to generate relatively uniform heating across the system. The system didn't hammer and never spat, at least until the "stuff" was added. So tomorrow I flush out the "stuff".

Thanks for your help! Appreciate it.

ethicalpaul

I'm sure @Jamie Hall didn't mean you shouldn't have cleaned out your muddy boiler but maybe was talking about cracking into the pigtail during this time of uncertainty. One thing at a time maybe he was thinking.

bdl

@ethicalpaul, thanks for the explanation. If I had all the parts, I would do the pigtail (and add in the 0-3 psi gauge). Missing some 1/4" close nipples to do the job. One thing at a time is usually the best way to fix systems. Just have to get through one more clanking night. One way or another the "gunk" will be drained tomorrow. I'll order the close nipples and install the pigtail splitter at a later time.

Is it better to have a splitter feeding two pigtails (to the gauge & pressuretrol) or to have one pigtail with a splitter to the gauge and pressuretrol? I have the parts, save for the close nipples to do a single pigtail. Advantage of single pigtail is I can see what pressure is actually on the pressuretrol. What's the advantage of a dual pigtail?

EBEBRATT-Ed

@bdl

One pigtail is fine. Do yourself a favor and put an extra tee on your pigtail manifold. Use the tee to add a 1/4" petcock or 1/4' ball valve. Then when the boiler is running with a little pressure you can open the petcock and blow the the pigtail clean. Saves having to disconnect wiring etc to remove a pigtail.

Yes you have wet steam. Probably due to the added chemical. Drain and flush the boiler. Maybe do it a second time after it runs 4 or 5 days. If it doesn't calm down after that you may have to skim the boiler

bdl

@EBEBRATT-Ed that's a good idea! I'll try to make that.

Yes, it's wet steam. On a cold start - lot's of clanking, wet floor in kitchen again .

JUGHNE

I have a 2' section of hose that fits tightly over 1/4" pipe, you can later unscrew the coupling/gauge, slip the hose over it and blow with your mouth. You should hear the water going back into the boiler thru the clear pigtail.
I also have the adjustable reusable cable tie with the small round balls that fit inside 1/4" pipe. It is flexible enough to push thru a pigtail. More effective than a flat cable tie.

bdl

Drained out the boiler. The drain and refill takes a long time. Took me about 4 hours. But was able to fire things up again. No dramatic drops in the sight glass, no water spurting out the vents, no hammer. Most of the radiators heated up. (Never came up to 1.5 psi. The 0-30 psi gauge on the boiler hardly lifted off the peg.) Probably have to do this flush again, but just ran a complete cycle until it satisfied the thermostat. (Only needed to raise the temp by 3F, it was a warm day here.)

Much quieter steam. Happy camper again! I have to find out what the name of that liquid boiler cleaner was, so it never gets used again in my home.

ethicalpaul

Nice job! I do like to raise the ph of my boiler water and I use small amounts of Rectorseal 8-way and litmus paper test strips to bring it up to 9 or so. Will it make my boiler last longer? I have no idea

bdl

Just read about this Rectorseal. So Rectorseal 8 way stays in the system, after the first flush? Can't you make the pH higher with bicarbonate? or is that bad?

ethicalpaul

Yes, it can stay in the system. They tout is as a cleaner (which you would then flush) and as a treatment that you can keep in there to boost ph. It seems pretty good but use WAY less than they say.

I wouldn't use bicarbonate of soda because it's a salt

MaxMercy

ethicalpaul said:

I do like to raise the ph of my boiler water and I use small amounts of Rectorseal 8-way and litmus paper test strips to bring it up to 9 or so. Will it make my boiler last longer?

Is there an advantage to being any higher than 7.0, or do you want it higher as a buffer (sorry for the pun) in case there's an undetected drop in pH?

ethicalpaul

My understanding is that water in contact with iron that has a ph of 8.3 or less will cause rust, so I like 9 or 10. I'm not sure how "right" of an answer that is

7 is "neutral" for ph, but still causes rust I think

Jamie Hall

The rusting also needs oxygen... but a just over neutral pH does help.

One of the reasons for using something like Rectorseal if you need to adjust pH is that it's a buffer, rather than a simple basic salt like bicarbonate of soda. Much less likely to get the pH too high, which can cause foaming and other mischief

bdl

@Jamie Hall thanks for the explanation. Guess I'll get some to put in.

bdl

Hmm buffer solutions are more complicated than I thought. The pH also varies as a function of temperature - it seems to get more alkaline the hotter it gets. (At least the example I saw.) Strangely enough, it turns out there is a mixture of sodium bicarbonate & sodium carbonate that makes an alkaline solution that can be adjusted from 9.2-10.6. https://aatbio.com/resources/buffer-preparations-and-recipes/carbonate-bicarbonate-buffer-ph-9-2-to-10-6
What's odder yet is sodium bicarbonate turns in to sodium carbonate at temps around 80-100C. Could this be the basis for the Dead Men adding sodium bicarbonate to steam systems?

Jamie Hall

Buffer systems are absolutely fascinating. In the bicarbonate/ carbonate one you are looking at (the sodium is just a convenient cation), it is the equilibrium between the carbonate ion, the bicarbonate ion, the hydrogen ion (that's your pH) -- and carbon dioxide in the dissolved gas and overlying air (that's why it's temperature sensitive).

And actually that buffer pair is a remarkably good one, although the concentrations of the anions are a little high for some applications, for pH in the range you mention. Which, however, is -- at least in my view -- a little too high for boiler water.

The beauty of buffers, though, is that one can add remarkable amounts of strong acid or base to the solution, and they will stabilise it -- at least up to a point.

All the domain of quantitative chemisry...

bdl

What is the best pH for boiler water? 8? 9? Is it correct to think that @ pH=9.2, the buffer bicarb/carb is too close to the edge for effective longer lasting control? I really know nothing about buffer solutions. I just poked around and read miscellaneous stuff.

Jamie Hall

i personally kind of think that around 8 is good -- and that the carbonate/bicarbonate buffer is a little high. Opinions vary.

I might add that some boilers -- Cedric, for example -- seem to run just fine on well water, which is slightly acid... without adding anything.