# Water heater flex "supply line" used for discharge line



## Bob Bartlett (Jan 2, 2013)

I am looking for information regarding the use of flexible water heater supply line (copper corrugated with brass nuts and rubber washers) as the discharge line on a water heater.

The device clearly says that it is a "water heater supply line", but I notice that plumbers and people use them for the water heater _discharge_ line also.  To make matters more confusing, a home center store used to sell a "water heater installation kit" that gave you two of these devices.  That would seem to imply that one goes on the discharge line.

The supply line device uses a rubber washer on each end, but there is no pressure or temperature rating on the copper flex supply line that I could use as guidance.

1) Is there any rule in any plumbing code that would suggest that these "supply lines" are not to be used as "discharge lines"?

2) Is it your interpretation of the plumbing code that these lines are specifically permitted for use on the discharge line?

3) If you are a plumber, have you/would you use these "supply line" products on a water heater discharge line?

4) Have you ever seen a problem with one of these devices when used on a "discharge line" that they felt was conclusively was due to its use on a discharge line?

Bob


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## steveray (Jan 2, 2013)

By discharge...do you mean the "hot" side? Or T&P discharge?

And welcome to the forum!

I also would look for listing info from the manufacturer....


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## codeworks (Jan 2, 2013)

we allox flex for the first 18" to 24" off the t&p before going to appd pvc pipe for discharge, at T&p


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## cda (Jan 2, 2013)

Welcome BOB from NO!!!

how did you find us??

do you mind stating what yyou do for a living??


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## jeffc (Jan 2, 2013)

The 2009 UPC, section 608.5 does not allow flex pipe for the P+t valve drain line.


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## Francis Vineyard (Jan 2, 2013)

Commonly see them use on replacement water heaters for the inlet and outlet ports.

2009 IRC.

*P2905.5 Water-distribution pipe.* Water-distribution piping within _dwelling units_ shall conform to NSF 61 and shall conform to one of the standards listed in Table P2905.5. All hot-water-distribution pipe and tubing shall have a minimum pressure rating of 100 psi at 180°F (689 kPa at 82°C).

*TABLE P2905.5 WATER DISTRIBUTION PIPE *


*MATERIAL*

*STANDARD*

Brass pipe

ASTM B 43

Chlorinated polyvinyl chloride (CPVC) plastic pipe and tubing

ASTM D 2846; ASTM F 441; ASTM F 442; CSA B137.6

Copper or copper-alloy pipe

ASTM B 42; ASTM B 302

Copper or copper-alloy tubing (Type K, WK, L, WL, M or WM)

ASTM B 75; ASTM B 88; ASTM B 251; ASTM B 447

Cross-linked polyethylene (PEX) plastic tubing

ASTM F 876; ASTM F 877; CSA B137.5

Cross-linked polyethylene/aluminum/cross-linked polyethylene (PEX-AL-PEX) pipe

ASTM F 1281; ASTM F 2262; CSA B137.10M

Cross-linked polyethylene/aluminum/high-density polyethylene (PEX-AL-HDPE)

ASTM F 1986

Galvanized steel pipe

ASTM A 53

Polyethylene/aluminum/polyethylene (PE-AL-PE) composite pipe

ASTM F 1282

Polypropylene (PP) plastic pipe or tubing

ASTM F 2389; CSA B137.11

Stainless steel (Type 304/304L) pipe

ASTM A 312; ASTM A 778



*P2905.7 Flexible water connectors.* Flexible water connectors, exposed to continuous pressure, shall conform to ASME A112.18.6. Access shall be provided to all flexible water connectors.

Francis


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## Mac (Jan 2, 2013)

The NY Res Code allows any material that is listed on table P2904.5 "Water Distribution Pipe". Each type has an ASTM designation, not sure where the corrugated copper fits in...


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## Pcinspector1 (Jan 2, 2013)

Can the copper corrugated discharge pipe meet IRC, P2803.6.1 #10 (Not terninate more than 6" above the floor or waste receptor?)

pc1


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## Bob Bartlett (Jan 2, 2013)

PC,

Are you thinking in terms of a relief discharge line?

This thread is dealing with the use of corrugated "supply line" for the hot water outlet of water heaters.

Please excuse my pointing that out.  I am just trying to herd the cats.

Bob


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## mtlogcabin (Jan 2, 2013)

> This thread is dealing with the use of corrugated "supply line" for the hot water outlet of water heaters


The "outlet" side of the water heater is the "supply line" for hot water in the home

Connectors - Water Heater, Brass & Tubular, Watts

Corrugated Water Heater Connectors

Features

• Available in 12", 15", 18" and 24" (305, 381, 457

and 610mm) lengths

• IAPMO Listed

• Certified by NSF to NSF/ANSI Standard 61

Pressure — Temperature

Max Pressure: 125psi / 8.62 bar

Max Temp: 180°F / 82.22°C


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## Pcinspector1 (Jan 2, 2013)

Bob, you are correct, I was making reference to the trp discharge line that runs down the side of the tank. My mistake, meow!


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## Francis Vineyard (Jan 2, 2013)

Mac said:
			
		

> The NY Res Code allows any material that is listed on table P2904.5 "Water Distribution Pipe". Each type has an ASTM designation, not sure where the corrugated copper fits in...


I would guess it's a tube that's designed to be bendable without tools.

Francis


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## steveray (Jan 3, 2013)

Looks like it meets the sections Francis posted......Should be good to go....as long as the manufacturer doesn't have any wierd restrictions......



			
				mtlogcabin said:
			
		

> The "outlet" side of the water heater is the "supply line" for hot water in the homeConnectors - Water Heater, Brass & Tubular, Watts
> 
> Corrugated Water Heater Connectors
> 
> ...


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## mark handler (Jan 3, 2013)

jeffc said:
			
		

> The 2009 UPC, section 608.5 does not allow flex pipe for the P+t valve drain line.


We have had this conversation before, I think on the ICC board, the water residual and "air", in the "ribs" prematurely rusts or corrodes the flex line.


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## JAT (Jan 4, 2013)

would not allow it

   504,6 2011 OPC

   #3 not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap

  #11  not have threaded connectionat the end of such piping


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## codeworks (Jan 4, 2013)

the threaded end referenced in the code is at the bottom of the discharge pipe, thats where it's prohibited


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## Bob Bartlett (Jun 4, 2013)

Thanks for your welcome, CDA.  I found this site by browsing looking for information about these connectors and it seemed like there were a lot of knowledgeable people that contributed.  I am a mechanical engineer, by the way, but I realize that there is a lot to be gained from the guys that actually use the products.


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## Bob Bartlett (Jun 4, 2013)

mark handler said:
			
		

> We have had this conversation before, I think on the ICC board, the water residual and "air", in the "ribs" prematurely rusts or corrodes the flex line.


Mr. Handler,  Have you ever heard of any issues with the rubber sealing washer used in the ends?


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