# a/c return



## irishplumber29 (Jun 23, 2010)

its black iron now and brass ball valve, you guys think i should replace it with the same, its been a long day....this is sch for monday night


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## Protech (Sep 22, 2008)

What are we looking at here???


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## irishplumber29 (Jun 23, 2010)

a/c return for a srtip mall. its mostly black iron but its rotting out in some places.


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## Protech (Sep 22, 2008)

So what, chilled glycol/water then?


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## irishplumber29 (Jun 23, 2010)

Protech said:


> So what, chilled glycol/water then?


ya 10-4


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## Protech (Sep 22, 2008)

I'd go with galvi next to the brass


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## irishplumber29 (Jun 23, 2010)

Protech said:


> I'd go with galvi next to the brass


i hate galv


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## Protech (Sep 22, 2008)

It's better than uncoated steel, which is what is in there now. At least the zinc coating will act as a sacrificial anode instead of the steel.

Are there any corrosion inhibitors in the glycol mix?



irishplumber29 said:


> i hate galv


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## irishplumber29 (Jun 23, 2010)

Protech said:


> It's better than uncoated steel, which is what is in there now. At least the zinc coating will act as a sacrificial anode instead of the steel.
> 
> Are there any corrosion inhibitors in the glycol mix?


no not that i know of


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## Protech (Sep 22, 2008)

Then I would say galvanized in-between the brass and the black for sure. Should help reduce galvanic cell corrosion. 

You could always go with a stainless steel valve instead of brass.



irishplumber29 said:


> no not that i know of


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## OldSchool (Jan 30, 2010)

It wouldn't matter what he replaced it with as the whole system is done in BLK.

Changing a small section of pipe would not save the entire system..... Get ready for a nice repipe.


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