# Water Heater Connections (CPVC)



## Pittsville (Jan 8, 2011)

I'm plumbing our house with CPVC and have moved on to the water heater. I'm considering making the following connections (as illustrated by my MSPAINT masterpiece :laughing.









I think I would rather use brass transition unions over the all CPVC versions with the elastomeric seal. Similarly, I feel more comfortable using the brass ball valve vs a CPVC version. All threads would be sealed with Oatey Great White pipe joint compound.

The unions are obviously designed to allow me to disconnect and move the water heater for maintenance. The additional union on the cold side (right below the valve) should allow me to disconnect the line and unscrew the ball valve. That way I won't have to cut the CPVC should I need to replace the valve.

I'm interested in hearing everyone's opinion on this configuration. Comments and suggestions for improvement are always welcome!


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## michaelcherr (Nov 10, 2010)

I am getting ready to do avery similar install.
I am thinking about something similar, except replacing the piece of cpvc between the shutoff and tank with galvanized.
It just seems like a waste to use a MPT to cpvc transition just to switch back with another cpvc to FPT a foot or so later.


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## Pittsville (Jan 8, 2011)

michaelcherr said:


> I am getting ready to do avery similar install.
> I am thinking about something similar, except replacing the piece of cpvc between the shutoff and tank with galvanized.
> It just seems like a waste to use a MPT to cpvc transition just to switch back with another cpvc to FPT a foot or so later.


You know... I hadn't even thought about using a nipple there. Simple, but efficient. Great idea!


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## LateralConcepts (Jun 6, 2010)

I'm not a fan of CPVC, but I'd just use 18" flex supply lines connecting to the nipples on the heater. Stub your CPVC down with MIP adapters. On the hot side you'd connect your flex supply directly to the MIP. On the cold side, you'd connect a MIPxFIP ball valve, then your flex supply line. Either way, check your local codes.


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## JoeLena (Nov 30, 2010)

And I believe you'll need a transition for the hot side, the adapters all say for cold water only, here's a transition I found: http://www.plumbersurplus.com/Prod/...oglebase&cvsfa=63&cvsfe=2&cvsfhu=313632363530


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## LateralConcepts (Jun 6, 2010)

JoeLena said:


> And I believe you'll need a transition for the hot side, the adapters all say for cold water only, here's a transition I found: http://www.plumbersurplus.com/Prod/...oglebase&cvsfa=63&cvsfe=2&cvsfhu=313632363530


Actually that one appears to be a garden hose thread. This is the one you'd need on both sides
http://www.amazon.com/gp/product/B000FKDJKS/ref=noref?ie=UTF8&s=hi&psc=1
http://www.amazon.com/gp/product/B000FKDJKS/ref=noref?ie=UTF8&s=hi&psc=1


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## JoeLena (Nov 30, 2010)

Doh! That's the one I meant:jester:!


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## Pittsville (Jan 8, 2011)

Yep, that's the one I'll be using. It's drawn (poorly) at the top of the cold side in my illustration above. With the configuration pictured, I was only using the one. Thank you both!


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## HVAC_NW (Oct 15, 2007)

That's one complex system. How about you scrap everything in between the water heater and the ball valve and use a 3/4"MIP to 3/4" FIP flex line? (you can get them in 12,15,18 and 24 inch lengths) You can use a stainless braided, or use a BrassCraft polymer line if you feel like you've gotta have that dielectric isolation, which the polymer line provides.

3/4" MIP from hose into ball valve, and 3/4" FIP with gasket seal onto water heater. I agree with using brass or bronze ball valve. I would personally avoid plastic female threads since they can split easily. 

I had better luck with pink or yellow, high density PTFE tape than pipe dope. I had a thread I couldn't get it to stop leaking with dope, but sealed right up with the pink tape.


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## Earnie (Jan 24, 2008)

Are heat traps still a good idea on the HW heater pipes?

Mechanical or simple horse shoe in the pipes?


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## Pittsville (Jan 8, 2011)

Earnie said:


> Are heat traps still a good idea on the HW heater pipes?
> 
> Mechanical or simple horse shoe in the pipes?


I haven't read/heard anything that would suggest an issue with using heat trap nipples. I'm using the style with the small flapper on the one end of the nipple. (this end installed closest to the water heater) What reason/shortcomings exist in terms of using the heat traps?


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## HVAC_NW (Oct 15, 2007)

Pittsville said:


> I haven't read/heard anything that would suggest an issue with using heat trap nipples. I'm using the style with the small flapper on the one end of the nipple. (this end installed closest to the water heater) What reason/shortcomings exist in terms of using the heat traps?


The shortcoming with the older metal ball type is that the make clicking noise whenever there is flow and sometimes, the ball becomes stuck and stops hot water. 

I'm not sure, but I think the modern rubber flappers that look like flappers aren't nearly as effective compared to using insulated inverted U pipes on both sides, but I have no idea how much energy you'll save with installing external heat traps.


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## Earnie (Jan 24, 2008)

Restrictive flow may be an issue. I searched for 1" heat traps but could not find any. There are plenty in 3/4". The U is just pipe so no mechanical components to fail.


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## Pittsville (Jan 8, 2011)

Earnie said:


> Restrictive flow may be an issue. I searched for 1" heat traps but could not find any. There are plenty in 3/4". The U is just pipe so no mechanical components to fail.


Never heard is using U shaped pipes in this manner. Can one of you elaborate?


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## HVAC_NW (Oct 15, 2007)

Pittsville said:


> Never heard is using U shaped pipes in this manner. Can one of you elaborate?


http://www.energycodes.gov/moodle/mod/resource/view.php?id=109

Just because of physics that hot water is lighter than cold water, it rises. Without a heat trap, the hot water rises up the pipe, it gets cooled, gets sent back to tank, and circulates like a lava lamp. 

The inverted U traps the heat from going past the top of arch. I think its best to do it using 24" flexible pipes. If you use a bunch of 90 degree elbows you'll have turbulent flow that contributes to flow drop. 

Also, spend the $20 or so and replace the drain spigot with a brass nipple and a 3/4" ball valve. Do it before you install it or as soon as you can. The most difficult part is probably removing the old plastic drain valve as it will break or twist around as you to remove it.


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## rmloan (Jan 21, 2012)

*Shark Bite*



LateralConcepts said:


> Actually that one appears to be a garden hose thread. This is the one you'd need on both sides
> http://www.amazon.com/gp/product/B000FKDJKS/ref=noref?ie=UTF8&s=hi&psc=1
> http://www.amazon.com/gp/product/B000FKDJKS/ref=noref?ie=UTF8&s=hi&psc=1


I'm late to this discussion and I am sure the original installer with a question has finished his installation. I used this fitting and it failed after about 5 years. It began to leak where the CPVC joins the brass. I recommend using a shark bite. It is a great fitting and easy to replace if it fails. It is available at Home Depot.


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## rmloan (Jan 21, 2012)

*Cpvc*

I debated replacing leaky copper with copper or CPVC. Subsequently, copper was banned in my town due to an epidemic of pinhole leaks. CPVC is now code for all new construction. I'm glad I went with CPVC. It is much easier to work with and significantly cheaper.
Regarding the configuration question. That will work on an electric water heater. For a gas heater, I recommend galvanized pipe with a couple of turns to create space between the vent pipe and the CPVC. Galvanized pipe>Ball Valve> Shark Bite fitting> CPVC. That space can also be created with the flex pipe recommended by another poster.


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