8-way and water line stability after numerous skims

wz25

Background:

Peerless 63-03, repiped and downfired to a 63-03L per this thread: https://forum.heatinghelp.com/discussion/170347/peerless-repipe

Single family 1915 colonial, about 1500 sf of living space. ~200 sf attached radiation, so boiler is only slightly oversized. No setbacks-- thermostat kept at 75F. Heating is even.

~50 ft of 2" main between a parallel-flow loop that feeds most of the radiators, plus a shorter counter-flow that serves two rads in the first floor addition. One BM vent at the end of each main, which seem to be working correctly. >95% of basement steam piping insulated with 1" fiberglass.

Boiler is ~2 years old. Since the repipe in late spring of 2019, I've skimmed at least a dozen times, mostly with 8-way in the system. I use ~3oz of 8-way for what should be 10-11 gallons of water at the normal water line-- so quite a bit less than the manufacturer's instructions.

Pressuretrol is set at between 0.5-1 cut-in and 1 diff. Have not seen the system cycle on pressure, and although I've not gotten around to installing a low pressure gauge yet, the pigtail was cleaned during the repipe, so it should not be clogged.

We have a whole-house filter (NOT a softener).

Observations:

Even with the multiple skims and the relatively conservative amounts of 8-way, every time I run the system with 8-way, I notice that the water line starts to drop, over the course of two cycles-- and slowly getting worse over a couple of weeks (which prompts me to skim). The images below are from an old IP cam I set up so I can monitor the water line without having to go downstairs. Due to the angle of the camera, the actual normal water line is slightly higher than it appears (indicated by the arrow/label in mid-cycle.png); the second image (idle.png) shows the normal water line level from the camera's perspective.

With 8-way, the water line slowly drops to the level shown in the first image; it moves maybe +/- 0.5" as it undulates downward, and stays there. What is shown now is 24 hours after a fresh skim. Just prior this last skim, I ran the boiler without any 8-way for about a month. Without 8-way, the water line does not drop-- it just moves the standard +/- 0.5". This skim did not show any observable oil, and the water was basically clear.

I can basically guarantee that if I skimmed today (with 8-way having been in the system for some time), I'd see some darker water -- even taking into account the natural tint that 8-way introduces. I expect that after another couple weeks, with 8-way, I will see more drastic water line movement, peaking out at maybe +/- 1". This is the point at which I would normally do another skim.

Questions:

• Has anyone experienced a situation where a dozen skims still does not seem to clear things out?
  
• Should I even keep attempting to use any 8-way in the system? I'd prefer to have some level of corrosion/scale protection, but at this point, it seems that 8-way, even in low concentrations, is creating a situation where I have to introduce more fresh water to handle the moderate surging that seems to happen
  
• Is what I am observing indicative of some more fundamental problem(s) that I am overlooking?
  

CantabHeat

My general experience with 8-way has been that it gets worse before it gets better.

The stuff really releases a lot of crud and it took quite a few full system flushes until things calmed down. Similar to what you’re describing in that I’d clean out and skim the system and it would be ok for a bit then more crud would build up.

Eventually that stopped and now it seems that there’s almost zero corrosion occurring in the system. When I flush the LWCO the water than comes out is clear (with that pink/purple tint). Same when cleaning my mud leg during my pre-season deep clean. I get a few flaks of things that have settled there but no more ‘mud’ of rust and grime.

So I don’t know how long it will take but my inclination is that eventually it will settle down for you and then things will run super clean... but only once existing crud is out of the system.

If you read reviews of 8-way on various sites you’ll see lots of reports from people saying they put the stuff in their boiler and things got worse so it seems a lot of people don’t understand the above. First it clean out your system, then it protects and stabilizes things long term. Many never get beyond the first and that’s probably what leads to those bad reviews.

I was skeptical during the constant flushing and cleaning stage after I took over a somewhat neglected system but now I’m a fan and the system runs super clean with a predictable behavior on the water line.

wz25

Thanks, @CantabHeat . That's reassuring to hear. A significant part of my concern stems from not knowing what is "normal," and while I expect (and have experienced) 8-way to make things initially worse, I guess I thought I'd get a sense check from the community when eventually was approaching double-digit skims.

dopey27177

Skimming is good but the second part of the process is open the wet return leg of return and drain the rust tat accumulated there.

The boiler water treatment causes the rust to become colloidal where the rust is in solution in the water.

Next trip drain the return and see how that works out.

Should this work you will save money on chemical.

Also check the PH that should be between 8 and 9.

Excessive PH can cause foaming or water bouncing in the boiler and gauge glass.

Jake

A pool chemical test kit is cheap and will do the job just fine,

SlamDunk

wz25 said:

Thanks, @CantabHeat . That's reassuring to hear. A significant part of my concern stems from not knowing what is "normal," and while I expect (and have experienced) 8-way to make things initially worse, I guess I thought I'd get a sense check from the community when eventually was approaching double-digit skims.

For me, normal is level goes down same distance and bounces +/- 0.25".

ethicalpaul

I think you are missing measuring your ph. As Jake said if the ph is too high your water will foam and might carry over into the main.

I know this because I put a sight glass on my riser and experimented with different levels of 8-way.

I also agree with what others wrote about doing some draining in addition to the skimming.

Congrats on your awesome repipe and boiler, neighbor!

EBEBRATT-Ed

@wz25

I think you answered you own questions.

" Without 8-way, the water line does not drop-- it just moves the standard +/- 0.5". "

I think the 8 way chemicals are causing more harm than good. You said with plain water the water level moves +/_ 1/2" that sounds normal to me.

It's a steam boiler, an open system you going to get some crud in it. Just do normal maintenance and see hoe it runs

ChrisJ

If 8 way is the same as Steamaster your pH can't be too high. At least not from the product.

You can easily use too much though. Reduce the amount you're using by half and see how it behaves.

What is your piping like? Good header and two risers etc?

wz25

Thanks all, for the additional insights.

@dopey27177 and re: pH in general-- I will get this measured by end of week to confirm. I don't suspect pH since we're on municipal water and the concentration of 8-way is roughly 1/3 to 1/4 what is recommended by the manufacturer, but I will let the numbers do the talking.

@SlamDunk : thanks for the additional data point-- I never know how much overall drop is considered normal, versus bouncing once the initial slow drop stabilizes.

@ethicalpaul : thanks! I should have mentioned that every time I skim, I do drain all a bit of water from all valves below the water line. With the repipe, that means four points, plus the cleanout for the (short but all above-ground) wet return. The latter was quite dirty when we first moved in, but over the last few years, with consistent cleaning, it's now more-or-less clear. And by that I mean a few rust particles and a bit of sludge (maybe the first couple ounces of waste if I were to let the system run 2-4 weeks in-between samples).

@EBEBRATT-Ed : I have been thinking the same thing, i.e. the point of cleaning is to ensure proper operation, and not to get the system sparkling clean.

@ChrisJ : Piping is overall good. All the near boiler piping is excellent, since it was properly done by @Dave0176 . Two 2" risers going into a 3" drop header. That being said, prior to this, the piping was various degrees of terrible-- which may or may not be significant, given that there was a period of time where wet steam was present in old pipes-- although I'd expect most of that would have worked its way out by now. I'll further reduce the concentration by half on the next round and see how that is, in conjunction with monitoring pH.

ethicalpaul

Everything sounds good. I look forward to seeing your ph. I can’t overemphasize how much the rectorseal instructions are crazy.

Chris, you can see the excellent install linked in the original post

SlamDunk

attached photo for your reference. i had a bad experience with 8-way. i dont use it. if I were to try again, i wouldnt use more than a shot glass worth to my 5gal of water.

wz25

pH results: cold tap is between 7.0 and 7.5. Boiler sample with 8-way as shown in original post is between 8.5 and 9. Attached shot for boiler pH makes the results look out of the upper range, but in reality it's not quite so dark.

Am doing a quick skim now and not adding any 8-way back, so the dilution should cut the concentration by a third. Will see how that runs over the next day.

Edit: as usual, the 8-way does seem to "bring down" gunk, as the first bucket of skim water is opaque, where it would be pretty much clear had the system been running without any 8-way.

Will get another pH measurement post-skim.

Don_175

I did multiple skims of my new CI boiler (2 years old). I added 1 cup of Rectorseal 8 way, and my pH is 11 per a pH meter. water is not dropping to the bottom of sight glass like it did previously. It still fluctuates some. Typically 1/2-1 inch but every so often drops 2 inches before recovering. My boiler manual says pH of 7-8.5. Is it OK to keep it around 11 with rectorseal or should I drop it some?

AdmiralYoda

My Peerless boiler is 40 years old and had not been maintained well by the previous owner. It was also leaking steam out of a couple radiators so it had been going through a few gallons per week of makeup water.

Our municipal pH is closer to 8 which is why I think this boiler has lasted so long even with poor maintenance.

Without Rectorseal my water would quickly get discolored and the float-type LWCO would get gunked up pretty bad. I added 6oz of Rectorseal to my 10-11ish gallons of water. It must have worked because the water got filthy pretty quick.

I skimmed the boiler and flushed it then added more Rectorseal back in. This process took a number of times before the water would stop getting nasty. I now go just about a whole season before the water starts to get cloudy/dirty.

I suspect as others have said....it will get worse before it gets better. But with a pH of around 10-11 there should be very little corrosion in the boiler and it should last a long time.

I use 8oz now and it seems to be working well. Zero bouncing of the water in the sight glass. Maybe +/- 0.25" and its crystal clean.

Don_175

Thanks. So you're not concerned that pH of 10-11 can make cast iron brittle? I also have some type of rubber gaskets between CI sections. Just want to be sure I'm not causing any issues.

ChrisJ

Don_175 said:

Thanks. So you're not concerned that pH of 10-11 can make cast iron brittle? I also have some type of rubber gaskets between CI sections. Just want to be sure I'm not causing any issues.

It will likely erode the gauge glass over time like it did to mine.
But that's easily replaceable, the boiler isn't.

I've never heard of high pH making cast iron brittle?
Can you supply a link on such info?

AdmiralYoda

@Don_175 Thats a good question. The latest Peerless 63 manual says to keep the pH between 7.5 and 11. Corrosion essentially stops with a pH above 9. So I'd gather between 9 and 11 is good and I shoot for right in the middle at 10.

Don_175

ChrisJ said:

I've never heard of high pH making cast iron brittle?
Can you supply a link on such info?

I read it on this site. Not sure which post it was from.

ethicalpaul

In my (homeowner) opinion, 11 is fine.