Closed Loop Chilled Water Treatment

[rleo49]

I'm new to water treatment so when I was asked to treat the loop with a corrosion inhibitor of course I have to "do it right". When I asked my boss how do I know when the right ratio he said they had always just poured it in until it looked dark. I convinced him to "let's do it right" and ordered a nitrate test kit which told you how to test but did not give any levels. Now to the questions.
If any of you have worked with treatment please help answer this for me.:)
What is the industry standard for cooling closed loop systems in PPM?
At what point is it to weak or to strong?
How often should you flush entire system and treat?

[hvac3901]

levels vary based on the type of make up water, and temperature of the water, and they also vary depending on your chemical sales person. So with that in mind, a good CHW level would be 350-500, and no more than say 3000 ppm tds, unless you are using hard faced pump seals in your facility, factory B&G seals are not hard faced, so unless you special ordered your pumps keep the TDS down below 2500.

for hot i have heard from 500-800 but i think personally there is not that big an issue usig a lower level like 500-600.

hope that helps.

[snipe70e]

I'm new to water treatment so when I was asked to treat the loop with a corrosion inhibitor of course I have to "do it right". When I asked my boss how do I know when the right ratio he said they had always just poured it in until it looked dark. I convinced him to "let's do it right" and ordered a nitrate test kit which told you how to test but did not give any levels. Now to the questions.
If any of you have worked with treatment please help answer this for me.:)
What is the industry standard for cooling closed loop systems in PPM?
At what point is it to weak or to strong?
How often should you flush entire system and treat?

We try to keep our chilled loop between 400 to 600, and the hot loop 600 to 800.

If your system has been maintained properly then you should not have to flush it. Your best course of action is get a chemical company in to ttest the water out. They will be able to tell you what the triberity of the system is and should it be flushed or filtered. they will also test for iron, ph, alkinity. Just adding by guess work can lead to crossion, scale, or high abrasion of your system.

Some treatments have thenalthaline(sp) in it, that gives it the red color when the system is basic. Others dont and are clear. If you are using the non thenalthaline chemical then your system should be clear.

By the way it is not nitrate that you test for, but it is nitrite that removes oxygen.

You are right to want to be doing the job correctely and in the long term will save your property owners money. I am working in a seet of buildings where we are trying to clean up the closed loop systems after years of oh this should be enough.

Good luck

[snipe70e]

Another thought. By using a test kit and a log sheet you will beable to tell if you have a developing problem. If your levels stay constant them your system is thight. If your TDS and nitrite levels both drop then your probably have a leak. If the TDS stays the dam and the nitrite drops then air is getting into the system.

So you see doing it by the guess way is the wrong way. Yuo are on the right tract.

You can go on line check out IUOE webs sight. Check to see if the local in you area is haveing a water treatment class. I know in the Bay Area Local 39 has classes on water trreatment some sessions and non members can take the class.

[freerider]

300-500 for chilled and 500-700 for heating per Nalco.

[rleo49]

Thanks for all the help:)

[mattm]

When I asked my boss how do I know when the right ratio he said they had always just poured it in until it looked dark.

You should be taking his job over pretty soon. :D

[rleo49]

You should be taking his job over pretty soon. :D

:)