Using chemical additives to clean the boiler, questions.

Chemicals or no chemicals

Hi,

We are being told that it is manufacturer's recommendations to add chemical cleaner to the boiler after install to clean out an oil residue on the inside. Is this always done? Is it a standard practice or is there controversy about it? We feel slightly uneasy with this recommendation. Also with further recommendation to continue to add chemicals annually to keep the system clean.

To our knowledge no service person has ever put chemicals into our system to clean it. I know we asked once too and can't remember what the reason was, but we were told not to add them.

I have concerns also that whatever chemical was added could leave a residue behind in the pipes and we could get some of that up into the house through the radiators. Also, wondering if you are just loosening up the stuff inside the pipes and causing more of it to end up in the boiler?

What is the problem with NOT using the chemicals? Any?

Thanks for your help :-)

It has become more of an issue

with the modern mod con boilers. Very small heat exchangers and multi metal construction make clean HX surfaces more of an issue.

Many of the new mod con boilers have aluminum HX Weil, Burnham, Crown, Buderus, SlantFin and others. Water quality and cleaning will be a big issue for this type of boiler.

Probably one that will sneak up on you after several years in service.

Proper glycol is another one to watch, especially with aluminum and it's ph sensitivity.

Clean em, treat'em and check them yearly. Both an inside clean and check and a ph test on the fluid should be mandatory.

hot rod

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steam system not hot water...

Hi, I should have made clear this is a steam system not hot water. Does that make a difference and were the above responses for a steam system?

I use TSP. No problems.

Just curious. If leftover manufacturing residue in the core is a problem it would seem that manufacturers should clean it before shipping. If they test each boiler off the line it should be simple to flush at this stage. Do any manufacturers do this? What is their view of initial cleaning?

Interesting. I was kind of thinking along the lines of pex and crimped copper. I was not thinking about lots of soldered copper. I know better but was not thinking sufficiently of all cases. My question was stimulated by my system. It is all pex and crimped copper and it was not cleaned when put into service because the assembly should not have generated junk. I don't know if there are any oil residues on the copper although I have never noticed anything when working with it. Perhaps in such systems it would be easier to just flush the boiler before installation. It is probably to late to do anything with mine because it is full of many gallons of glycol which I sure don't want to throw away.

Glycol

Ken, you wrote;
"Even well inhibited glycol becomes highly acidic over a relatively short period"
How long a period?

Words

I don’t want to confuse the idea of providing good water to the boiler and stating that every boiler needs chemicals added or it won’t run right. Do we want a low TDS count
and the PH in range? Yes. Do I want to use a ton of corrosive chemicals to get it there no.

It's the blend water also

that will use up the inhibitor package from the get go. Really the glycol itself doesn't go bad, it's basically a petro product. it's the inhibitors that go bad and cause the ph swing. From what I have learned.

Consider what solder flux is comprised of... Zinc Chloride for the most part. Not a good mix for inhibited glycols.

Or stainless boilers and indirects for that matter

Overheating and frying glycol is another quick death. solar panels that stagnet and get in excess of 350 will ruin glycol inhibitors in a short period of time.

Glycols that go acidic can be salvaged with additional inhibitors. It just takes a boat load if the ph drops into the 7's or lower. At some point it becomes less expensive to dump, clean and start over.

hot rod

Inhibitors and antifreeze

Cleaning a system is important. New systems to flush out residue or older systems that have scale buildup. (See attached chart) That said, here is some information about antifreeze

Most antifreezes (propylene, ethylene ,synthetics) break down because of amount of heat and oxygen. Because we need to heat the fluid there is little we can do, other than not run the system at a higher temp than needed. In closed systems most of the oxygen is released from the fluid. Adding new water or leaks in the system will introduce new oxygen. Acid is the end result of the antifreeze breakdown. The inhibitor in standard system antifreeze has a high pH. This works as an anti-corrosion agent and a buffer to the acid created. So, from a heat stand point the hotter you make the fluid and the longer you heat it, the quicker it will breakdown.
I received sample of propylene glycol antifreeze, daily, for testing. I have seen samples that were 3 weeks old that was brown and smelled like burned transmission fluid. Found they had a burner problem on a new system and burned the fluid. On the other end of the spectrum, I've tested a samople from a home owner that took care of his own system by checking the fluid for pH and glycol content and adding inhibitor when needed. The result was a very good fluid that had been in the system for 17 years.
The reason that you would not want to use Automotive antifreeze in a boiler is that auto antifeezes use silicates. The reason for this is that it is an inexpensive inhibitor. Silicates coat the inside of the system with a coating that we used to refer to as Snot. This inhibitor works in vehicles because they are run on a regular basis 365 days a year. If left in a system for an extented period of time ( The off heating season) the silicate will drop out of the fluid and settle to the low point. Once this happens, even if heated, it will not disolve back into the fluid, cloging the system. If anyone would like formulas and data on automotive antifreezes, give me a call. 800-678-6625.
Inhibitors for aluminum/multimetal systems is another 5 pages for the highlights. Maybe next time.

Found No Need.

I found it is not needed to add chemicals to clean a steam boiler.Why take a chance ?

Blow down and skim is all that's needed in my part of the world.


If it ante broke , don't break it...

I think adding chemicals are a easy sell so the installer does not have to return at a later date to clean boiler... Sorry not happening ....