Dialing in Boiler Water pH

acwagner

I've been using 8-way to treat and raise my steam boiler water pH, and trying to achieve the goldilocks zone of higher pH without surging.

I was using generic litmus paper to test the pH, but found they were not very effective for dialing the pH exactly and also under reporting the pH value. So I ended up over treating my boiler water to the point I got surging.

I got a different higher quality litmus paper that is that limited to 7-14 pH range, which indicates my boiler water pH is around 11.5. (For comparison, the generic litmus paper was reading around 8-10). The water line is somewhat unstable but not bad. That said, I'd like to reduce the pH to be closer to 10.

So, my question is: what's the consensus on the best way to reduce the pH of boiler water in this situation? I see two options:

1. Drain 50% of the boiler water and dilute the remaining boiler water by adding new feed water. Theoretically gets me a pH of around 10.3.
2. Add an acid directly to the boiler water to neutralize.

Thoughts?

ethicalpaul

It's actually kind of hard to move the pH because 8-way has a pH buffer that acts to keep the PH at a certain level even after diluting. You might find you have to drain almost all the water in order to get the pH to be lower.

If you really need your pH to be lower than where 8-way tries to keep it, then you might consider a different product that raises the pH but without a buffer. You can use pH booster, used for swimming pools to carefully increase your pH, with sufficient sample tests to get where you want it.

But having said all that, I can 100% guarantee that it's not the 10.3 pH alone that is making you surge. You have some other thing in the water that is causing or helping to cause it. I have a video where I added a ludicrous amount of 8-way to see if there was any surging, and there wasn't. I'll link the video here.

Dan_NJ

https://forum.heatinghelp.com/discussion/comment/1820790#Comment_1820790

Per the OP it's 11.5 now. 10.3 is the target number.

Jamie Hall

https://forum.heatinghelp.com/discussion/comment/1820805#Comment_1820805

The problem is, as @ethicalpaul said, is that 8-Way is a buffer. And as I have pointed out elsewhere, pH in the presence of a buffer is remarkably stable — that's what buffers are for. To hold the pH constant, or reasonably so, regardless of concentration.

As he also said, you'll likely have to pretty well drain all the water out and start all over with a different buffer — or none at all and see what the natural running pH of the system is.

ethicalpaul

https://forum.heatinghelp.com/discussion/comment/1820805#Comment_1820805

Thank you, you're right. But 11.5 in itself also doesn't make water surge in a boiler either. I had my ph off the scale, something like 13 or 14 with not a hint of surging, as seen in the linked video.

acwagner

My boiler does surge at higher pH levels. I've taken to 13+ and it surges. At lower alkaline pH levels it's fine. Hence why I'm experimenting with how high I can take it without adverse effects. At 11.5, the water line is a little more unstable than normal, but no problems in terms of overall operation. I think a pH of 10 is probably the sweet spot for my setup.

It sounds like the buffering capability of 8-way makes dilution not very effective at reducing the pH. I was just trying to see if there was an option short of emptying the entire boiler and refilling in situations when I overshot the mark.

ethicalpaul

It wouldn't hurt to try it in stages. Like drain half then refill and test, and repeat. Eventually the buffer won't be able to hold the pH.

I'm interested to hears yours is surging at 11.5.

Is there still mud/chocolate milk being broken loose or appearing in your boiler?