water htr ptr valve drain

[codeworks]

water htr inspection, new home, ptr line is flex stainless down 18" maybe a little more, then changes over to pex. i thought pex was not approved for this application, due to temp/pressure ratings. any thoughts, help is appreciated

 

[mark handler]

I believe, According to the IRC you must have 18 inch clearance from the top of the water heater to your Pex connection.

 

[codeworks]

i understand that. my question was about the ptr line. it is my understanding that pex in NOT APPROVED for ptr drain (pressure temperature relief drain) . what i saw was a flex connector from the ptr valve, with pex below that, which i think is a no no.

 

[Francis Vineyard]

IPC or UPC?

Pex is good, PVC is no good! Don't know about is flex stainless, does it meet the listing in table 605.4 (2009 IPC)?

504.6 Requirements for discharge piping.

13. Be constructed of those materials listed in :Next('./icod_ipc_2009_6_sec005_par004.htm')'>Section 605.4 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

605.4 Water distribution pipe. Water distribution pipe shall conform to NSF 61 and shall conform to one of the standards listed in Table 605.4. All hot water distribution pipe and tubing shall have a minimum pressure rating of 100 psi (690 kPa) at 180ºF (82ºC).

TABLE 605.4 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; CAN/CSA B137.10M
Cross-linked polyethylene/aluminum/high-density polyethylene (PEX-AL-HDPE)	ASTM F 1986
Ductile iron pipe	AWWA C151/A21.51; AWWA C115/A21.15
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 pipe (Type 304/304L)	ASTM A 312; ASTM A 778
Stainless steel pipe (Type 316/316L)	ASTM A 312; ASTM A 778

Francis

 

[codeworks]

thanks , found the response . it's ipc, flexible water connection to pex, piping is rated for 180f at 100 psi, which is in line wih commectary remarks, thanks a bunch !

 

[SCBO1]

I believe this site has more threads on this subject. The pex instructuctions, I believe allow it and the IPC chart 605.4 allows it.

I thought you could'nt reduce the size of the discharge line from a TP which the pex fitting does. Pex fittings are insert type fittings, unless they have a new external fitting out on the market.

So how is it installed to meet code?

pc1

 

[codeworks]

very good question, and answer, its not an approved installation based on that. thanks a ton !

 

[Francis Vineyard]

The couplings as shown above on the TPR and stainless flex tubing above seals on the outside, but the crimped insert would reduce the inside diameter.

Francis

 

[mtlogcabin]

301.5 Pipe, tube and fitting sizes.

Unless otherwise specified, the pipe, tube and fitting sizes specified in this code are expressed in nominal or standard sizes as designated in the referenced material standards.

You guys are overthinking this

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

If the outlet valve is 3/4" then the plumber can choose SCHD 40 NPS piping of tubing which will all very on there ID depending on materials. The manufactures fittings are designed to be used with their piping systems without creating a significant loss in flow

http://www.gizmology.net/pipe.htm