HB Smith 450

johnh168

Boiler build up of calcium and section nipple clogged. we have been using chemicals since they have been installed 17 years. My chemical guy said the only way to get the calcium out of the section is to do a 7% Hydro chloric acid wash and that should remove it my worries is would the hydro chloric acid affect the boiler. Has anybody had this done or had the same problem.
Thanks

SWEI

Is this a process boiler or a heating boiler? What pressure does it run at?

nicholas bonham-carter

Is this the boiler:

http://www.smithboiler.com/modules/lit_lib/download.asp?litFileID=890

Does it seem as though a nipple from the section to the return drum may be plugged?
Can that nipple be cut out and replaced?
If acid would be used, will there be a problem in disposing of it?
If you can see a way to rod out the deposits, then I would do that first. Following that, I would then fill it with reverse osmosis water, in an effort to dissolve out the 14 years of solidified boiler chemicals.
This is why I am not in favor of boiler chemicals, without some sort of clear reason for using them, (excessive chlorides, constant loss system, etc.).
As SWEI asked, what is this boiler used for, and what pressure. What is the feed water chemistry like in your area?--NBC

nicholas bonham-carter

From further study of the Smith 450 manual, I see that there are rubber, or non-metallic gaskets in the return drum, which may react badly to hydrochloric acid. Maybe regular citric acid, or white vinegar would be better.
I would put your chemical guy on notice that there may be problems arising from his treatments over the years causing this problem. It looks like an expensive replacement, if that would be necessary.
Hopefully, the rodding out of the plug, and subsequent dissolving of the rest of the sediment with R/O water will solve this.
I hope you will keep posting about this here so we can benefit from your unhappy experience, and its eventual solution.--NBC

nicholas bonham-carter

John--did you ever find a solution to this problem?--NBC

Henry

The "chemical guy" my best saleman for replacement boilers! From Smith: 5. Water treatment for cast iron boilers should be designed to provide pure makeup water rather than attempting control by adding chemicals to the boiler water."
"We do not recommend frequent blowdown. We suggest water treatment only when the local water supply contains such unusual amounts of corrosives and scaling, or sludge forming elements, that treatment is definitely in order and any treatment should be based only on regular water analysis by a reputable water treatment concern."