# new electric water heater - Vacuum breaker necessary?



## J187 (May 19, 2006)

Installing a new 50 Gal electric water heater. I'm moving the unit to the back of the room. Do I need to install a vacuum breaker on the cold supply, I've heard yes and I've heard no.


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## Ron The Plumber (Jun 7, 2006)

Vacuum breaker?

I don't know what you mean by this.


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## J187 (May 19, 2006)

Hey Ron, I think maybe different names are the problem. Anti-siphon device? Backflow preventer?

http://en.wikipedia.org/wiki/Atmospheric_vacuum_breaker

I just say vacuum breaker because the device I happened to have is a vacuum breaker, w. the little hood on top. 

If you do say yes, the other question is, do I have to install it upright or can I install it upside down or verticle??

Thanks again!


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## Ron The Plumber (Jun 7, 2006)

Thats only for sprinkler systems, you don't need that for the water heater


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## J187 (May 19, 2006)

Thanks! There was one on the old line to the water heater but I hadn't seen one before that. After seeing it, I asked around, heard some yeses and some nos. I defer all to your knowledge. Thanks Ron.


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## SalemCat (Oct 5, 2009)

*Mandatory in Massachusetts - Must be installed Upright*



J187 said:


> Hey Ron, I think maybe different names are the problem. Anti-siphon device? Backflow preventer?
> 
> http://en.wikipedia.org/wiki/Atmospheric_vacuum_breaker
> 
> ...


Mandatory in Massachusetts

Must be installed upright (so it looks like a Mushroom)

Watts N36

Water Service Vacuum Relief Valves

http://www.watts.com/pages/_products_details.asp?pid=815


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## AllanJ (Nov 24, 2007)

The purpose of a vacuum breaker at a water heater is, in the event extreme suction should be applied to the water system, for example a fire engine pumper fighting a fire down the street, the water heater tank doesn't collapse or implode.


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## Alan (Apr 12, 2006)

Gravedigging.


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## SalemCat (Oct 5, 2009)

AllanJ said:


> The purpose of a vacuum breaker at a water heater is, in the event extreme suction should be applied to the water system, for example a fire engine pumper fighting a fire down the street, the water heater tank doesn't collapse or implode.


Good Point.

They're only about $15. Of course you may need extra fittings which will likely double the cost. I think it's worth the expense. Especially since I believe you can use the same Vacuum Breaker over and over again.


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## TheEplumber (Jul 20, 2010)

Who dug up this 5 yr old post? :laughing:


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## AllanJ (Nov 24, 2007)

TheEplumber said:


> Who dug up this 5 yr old post? :laughing:


Someone using Google to get plumbing do it yourself help.


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## Javiles (Dec 12, 2011)

SalemCat said:


> Mandatory in Massachusetts
> 
> Must be installed upright (so it looks like a Mushroom)
> 
> ...



Wow never heard that one; I would imagine it would then be required for the whole house. You have to install a vacuum breakers on bottom fed water heaters. But then again every code varies.:yes:


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## Javiles (Dec 12, 2011)

TheEplumber said:


> Who dug up this 5 yr old post? :laughing:



Dam it just waist-ed 10 min typing.


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## teanbiscuits (Dec 20, 2021)

Ron The Plumber said:


> Thats only for sprinkler systems, you don't need that for the water heater


My understanding is that in cases where the hot water heater is above your fixtures, it is necessary to prevent siphonage. I am not an expert, but was advised by one recently in my case, a condo building.


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