Water softener use for a steam boiler - good idea?

elfie

heard many views on this



if you have a steam system that is untreated, would it at least make sense to have the makeup water line flow thru a water softener?  (ie. to at least remove particles)



is there any benefit to a softener is quality of water going into boiler is very hard

nicholas bonham-carter

invitation to graphitic corrosion???

there's a reason most people don't want to drink softened water--it has a slightly salty taste. your boiler will not like it either! [search graphitic corrosion]

if a steam system is properly maintained, then not much water will be needed for makeup, so the effects of hard water will not be so pronounced.

if this is for a new system, then get a letter from the mfg's foundry/metallurgy department stating their views on the subject [ie. will the warranty remain in effect?]--nbc

kcopp

another thing....

If you don't put the softened water in (use raw filtered) keep the salt bags and the softener A LONG WAYS Away.... I saw one job where they piled the solar salt right next to the boiler....

Jamie Hall

As a rule, no

not for residential boilers.  The amount of makeup water should be extremely small, and thus the potential for scale formation from the hardness is vanishingly small.  However, as has been said, water softeners work by swapping sodium (salt) for calcium (hardness).  Softened water, then is more corrosive than unsoftened water.



Treated (NOT softened) water is required for power boilers, or boilers where there is a consumptive use of steam, such as ships and steam locomotives.  You are not in that category!

seabee570

SOFT WATER

generally ,in residential boilers softners are not used....but the key to this question is;

 ' is there any benefit to a softener is quality of water going into boiler is very hard?.

if the water is very hard,most boiler manufacturers,even residential do not want very hard water going inot a steam boiler. I would say if you have excessive hardness, it would be a good idea to have  a softner.

even residential steam boilers require make-up water. so really hard make-up water is not good....[u][color=#0066cc]Reply[/color][/u]if the boiler is a steel boiler,then it would not hurt to have softner.

elfie

water softener for untreated steam boiler - good idea?

the steam boiler is a commercial boiler (14 sections cast iron)



it is not being treated chemically



and the makeup water quality is on the very hard side.

nicholas bonham-carter

Between a rock and a hard place

There you have the choice: Holed sections from excess chlorides from the softener, excessive calcium deposits from hard water, or fix every leak in the system so that a minimum amount of makeup water is added, and just use regular water, hard as it is.--nbc

Jamie Hall

I your water is

really seriously hard, and if you are getting significant scale formation in the boiler, and if you are adding a significant amount of that hard water...



You may need to get a little bit serious about water treatment for the boiler.  You need to have releatively low total dissolved solids -- you could check with the boiler manufacturer on it, but a starting point might be as low as 100 mg/L -- and a close to neutral pH (say 6 to 7.5).  One very real possibility, although it isn't super cheap, would be to look into reverse osmosis treatment; depending on the exact level of hardness, you might not have to treat all the makeup water, but be able to treat some and blend to get good quality.  The problem with most simple water softeners is that they add sodium and raise the pH while treating the water, and that just isn't desirable.

Hap_Hazzard

Good call.

I was going to suggest RO. You could either mix it with tap water or adjust the pH with sodium carbonate. Manufacturers generally don't tell you what pH they recommend in the I & O manuals, but from what I've read they like it to be between 7.0 and 8.5. Depending on the ionic composition of the water, nanofiltration might be another option.

nicholas bonham-carter

What sort of water to use?

Is there a large amount of water needing to be added to this boiler? Have you considered a meter on the makeup water?

Certainly you should check with the boiler mfg. for the question of softened makeup water, and also how much water the boiler should have as a maximum, per year!--NBC