# Back Flow Preventer



## Ron (Jun 12, 2008)

Does your code require a back flow preventer on hand held shower heads? Here they require it.


----------



## Bill (Jun 17, 2008)

Yeh, here too Ron. If I remember right, they are built into the wand.


----------



## Plumbworker (Oct 23, 2008)

Ron The Plumber said:


> Does your code require a back flow preventer on hand held shower heads? Here they require it.


only in tub applications then yes a vac breaker is requied but in showers no


----------



## Ron (Jun 12, 2008)

It's all hand helds here, my father in law was told by the inspector during final, he needs one, she passed it without, but asked that he put one on, yea like he is going to do it after the fact.


----------



## Regulator (Aug 20, 2009)

BC plumbing code does not specify such, but many local jurisdictions require it. What is generally acceptable here is a dual check on the hot and cold side upstream of the faucet. 

Some jurisdictions take the action of the diverter valve into account such that if the diverter closes when pressure ceases, the dual checks are not required. I personally disagree with the notion of a diverter valve acting as a backflow preventer.

The CSA B64.10-01 suggests that all bathtubs are identified as a moderate hazard (equal to low hazard in PNWS CCC Manual language). But even as a moderate hazard the dual check valve does not offer sufficient protection. An AVB would be the minimum acceptable device.

This is a good example of where convenience has overuled the required formula for backflow preventer selection.

BTW, in my area, bathtubs within convelesant and medical facilities are identified as severe hazards, requiring either spill resistant or pressure vacuum breaker assemblies or RPZs.


----------



## Optimus Primer (May 20, 2009)

I believe ours is if the hand held can reach water then yes. So if it hangs above a curb in the shower then you wouldnt need one. Like someone said, alot of the newer fixtures have them installed already.


----------



## Regulator (Aug 20, 2009)

house plumber said:


> I believe ours is if the hand held can reach water then yes. So if it hangs above a curb in the shower then you wouldnt need one. Like someone said, alot of the newer fixtures have them installed already.


Indeed, many faucets do have them as an integral part of the trim, but have they been approved by the agency acceptable to the AHJ? My point being, I would not rely on a no-name Chinese manufactured AVB. :no:

Good topic, BTW.


----------



## kfosh (Jun 17, 2008)

required here


----------



## Protech (Sep 22, 2008)

Technically yes, enforced no.....sadly.


----------



## Christina (Jul 14, 2009)

Plumbworker said:


> only in tub applications then yes a vac breaker is requied but in showers no


Same here...


----------



## Optimus Primer (May 20, 2009)

Regulator said:


> Indeed, many faucets do have them as an integral part of the trim, but have they been approved by the agency acceptable to the AHJ? My point being, I would not rely on a no-name Chinese manufactured AVB. :no:
> 
> Good topic, BTW.


umm yes, they would have to be approved. nothing goes in unless it stamped with astm or the other ones.


----------



## Down N Dirty (Mar 12, 2009)

Here they are not enforced unless the hand held can reach within one inch of the shower base. On all tubs they are required.


----------



## Regulator (Aug 20, 2009)

BTW, all my posts on this subject relate to those applications with hand held shower heads.


----------



## TheMaster (Jun 12, 2009)

I went to an asian sauna to repair a price pfister shower valve. They had a handheld shower attached to the shower arm. The faucet was "running" water not dripping. It was making so much noise that they brought in a big blue bucket about knee high and dropped the handshower into it. The bucket was full and the head submerged. The asian girls tipped me 40 bucks on top of what the building owner paid me to repair it. SWEET!


----------



## 422 plumber (Jul 31, 2008)

me plumb you long time


----------



## pauliplumber (Feb 9, 2009)

Not sure if it's code here, it would take me an hour to find that one in our book, but I have noticed all of the new ones I have installed recently have one built in.


----------



## Mega Smash (Oct 9, 2009)

I recently learned about this from my CC/BF course. And what was said is that to meet CSA requirements, there must be an inline check in the telephone sprayer. Just like a vegetable sprayer on a KS.

The instructor also said that if there is a pull-up type toe tester on the shower, that that serves as an AVB; Remove water pressure, and it opens to atmosphere. Even if the shower was in use, with a telephone sprayer and a back siphonage was introduced, the toe tester would open to vent, and the inline check would do its job.

Also add to that, the air gap between the telephone head and the tub.


----------



## SlickRick (Sep 3, 2009)

Mega Smash said:


> I recently learned about this from my CC/BF course. And what was said is that to meet CSA requirements, there must be an inline check in the telephone sprayer. Just like a vegetable sprayer on a KS.
> 
> The instructor also said that if there is a pull-up type toe tester on the shower, that that serves as an AVB; Remove water pressure, and it opens to atmosphere. Even if the shower was in use, with a telephone sprayer and a back siphonage was introduced, the toe tester would open to vent, and the inline check would do its job.
> 
> Also add to that, the air gap between the telephone head and the tub.


 
Telephone who?... your toe up what? :blink: I gotsta know...Are we talking hand held shower and diverter spout..?


----------



## Regulator (Aug 20, 2009)

Mega Smash said:


> I recently learned about this from my CC/BF course. And what was said is that to meet CSA requirements, there must be an inline check in the telephone sprayer. Just like a vegetable sprayer on a KS.
> 
> The instructor also said that if there is a pull-up type toe tester on the shower, that that serves as an AVB; Remove water pressure, and it opens to atmosphere. Even if the shower was in use, with a telephone sprayer and a back siphonage was introduced, the toe tester would open to vent, and the inline check would do its job.
> 
> Also add to that, the air gap between the telephone head and the tub.


I have not seen anywhere in the CSA B.64.10-01 (the edition mandated by the BC Plumbing Code) that it is acceptable to assume that a diverter valve acts as any sort of backflow preventer. Maybe your instructor is aware of a clause in the manual that I have seen?


----------



## SlickRick (Sep 3, 2009)

somebody answer my above question...


----------



## Regulator (Aug 20, 2009)

slickrick said:


> Telephone who?... your toe up what? :blink: I gotsta know...Are we talking hand held shower and diverter spout..?


That's my guess. Never heard either expression before, though.


----------



## SlickRick (Sep 3, 2009)

Regulator said:


> That's my guess. Never heard either expression before, though.


Thank you Reg. I have a tournament in the morning and I was not going to bed until I had a response...

I won... HOA..... I'm just sayin'


----------

