Thread: Pressure relief discharge to laundry sink

This installation was unique and I was curious if it should be flagged or not.

The discharge was secured in place at the laundry sink with one other elbow directing any flow toward the drain.

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Originally Posted by Jon mackay

This installation was unique and I was curious if it should be flagged or not.

The discharge was secured in place at the laundry sink with one other elbow directing any flow toward the drain.

It's wrong.

Possible cross contamination with it being in the sink. Also looks like PVC (CPVC is OK) pipe and if it is that is not allowed.

The only concern that I could see is if the valve suddenly opened while someone was at the sink. I think that it's worth commenting on but certainly not a big issue to change. If it was my house I'd most likely never get around to changing it.

I would call it out. Straight down to within 6" of the floor is the most correct installation and least likely to scald someone.
Maybe the PRV has developed a leak? May need to be replaced. I'd check for a stain or wet spot.
I'd check that outlet over the sink, too. I guess it's an old house, but it was my place, it would get a GFCI receptacle.

Looks like the water heater's days are numbered anyway.

Originally Posted by John Kogel

Maybe the PRV has developed a leak? May need to be replaced. I'd check for a stain or wet spot.

Eyeballing the distance between the TPR and the connector fitting, it looks like the pipe would have orginally just reached the top of the overflow pan. It started dripping/leaking so someone twisted the pipe to the side and added an extension into the sink.

Again if that is PVC, that is a no-no. CPVC is acceptable.

Originally Posted by John Arnold

.
]Looks like the water heater's days are numbered anyway.

.
Rust on the Steel Outer Jacket say's it's a Goner.
.

The problem with unconditionally saying that CPVC is acceptable can be problematic. In my state the pipe "shall" be metal - plastic is not permitted. What's sad is that the hardware and big box stores sell the plastic pipes by the truck load and have no idea that it is illegal.

Originally Posted by Eric Barker

The problem with unconditionally saying that CPVC is acceptable can be problematic. In my state the pipe "shall" be metal - plastic is not permitted. What's sad is that the hardware and big box stores sell the plastic pipes by the truck load and have no idea that it is illegal.

That's a funny one. Eric. The plastic pipes work fine. I recommend them because they are user friendly. But we also use NMD for wiring, so it's like we are on a different planet.

John, I'm a bad boy - I don't report on the plastic extensions. There are too many other more things for me to watch for.

Somewhere I got the idea that if plastic, the pipe must be labeled for TPR valve application. I see lots of them that are labeled as such.

I was at a local Home Depot this week and saw some plastic extensions - there was no markings what so ever. I have no idea if it was P.V.C., C.P.V.C. or C.R.A.P.

If that is PEX then the material is allowed, but there are some problems with the installation:
- PEX needs to be supported and secured at maximum 3 foot intervals for sizes 1" and smaller.
- The end over the laundry tub would need to be turned down and have a minimum 1-1/2" air gap above the overflow rim of the laundry tub.
- Discharging in that manner would require additional supports for that end due to the thrust when the T&P let go.
- Discharging in that manner could also be hazardous to persons, and that is not allowed either.
- That PEX is not allowed within 6" of the draft hood.

That will do for starters.

I had a similar situation last week. The TPR Valve drainline discharged onto the edge of a laundry sink. Called it out as being unsafe. The probability may be one in a thousand, one in a hundred thousand or one in a million, but the chance of it happening is still there.

I'm a newbie here, but that vent looks way sketchy to me. How did it terminate?

Like others have said, if this discharge pipe is PVC, it is a no no. The TPV normally opens only when the temp is too high, and along with too high temp, the pressure is elevated. With those factors combined, upon the TPV opening, the PVC material will melt where it is threaded into the TPV, causing it to pop out of the TPV, and scald anyone who is in range. This scenario is in addition to the PVC being located too close to the flu, and being softened by that heat to start with. As for the discharge end of the pipe, as Jerry pointed out, the end of the pipe should be above the flood plan of the sink. Whether the pipe terminates above the sink, or down in the sink as stated, when a high pressure gush of hot water blasts out of the pipe, it is going to splash up out of the sink. It could be properly terminated under or behind the sink, in a stand pipe with trap.

T&P pipe has to be metal in CA. If this is in a basement, then other factors come into play.
CA normally required the pipe go to the floor, drainage or outside, but obviously the pipe must have proper slope, so directing toward a metal sink would be allowable per Mr. Peck's pointers in an effort to avoid flooding.

If there is no way to get the T&P to the exterior, i.e. no exterior wall available, I would allow the sink as the termination point. The material allowed could be metal or CVPVC. The pipe should follow the contour of the wall, terminating at the rear left corner of the sink and be secured to the wall. As it is now, the sink is not usable.

There are no seismic straps. The vent connector is not screwed to the draft hood. The picture doesn't show the continuation of the vent and the vent may have a 90 degree bend [not permitted] where the connector connects to the vent. Not knowing when the water heater was installed hampers this call but the gas shut off valve is no longer allowed because it requires a tool to operate it.

Originally Posted by Jimmy Roberts

Like others have said, if this discharge pipe is PVC, it is a no no. The TPV normally opens only when the temp is too high, and along with too high temp, the pressure is elevated. With those factors combined, upon the TPV opening, the PVC material will melt where it is threaded into the TPV, causing it to pop out of the TPV, and scald anyone who is in range. This scenario is in addition to the PVC being located too close to the flu, and being softened by that heat to start with. As for the discharge end of the pipe, as Jerry pointed out, the end of the pipe should be above the flood plan of the sink. Whether the pipe terminates above the sink, or down in the sink as stated, when a high pressure gush of hot water blasts out of the pipe, it is going to splash up out of the sink. It could be properly terminated under or behind the sink, in a stand pipe with trap.

That would require a trap primer because the trap would never see water unless the T&P opened.

Originally Posted by Jimmy Roberts

It could be properly terminated under or behind the sink, in a stand pipe with trap.

Not "in a stand pipe" but "into a standpipe through an air gap", just clarifying the wording of what would be acceptable according to the code.

Originally Posted by David Bertrams

If there is no way to get the T&P to the exterior, i.e. no exterior wall available, I would allow the sink as the termination point.

The code does not allow the T&P to discharge to the exterior when the water heater is inside, the T&P is required to discharge to the same room or space in which the water heater is located, and the discharge would need to be through an air gap to the receptor (or floor, or to wherever it is discharging).

Originally Posted by Jerry Peck

Not "in a stand pipe" but "into a standpipe through an air gap", just clarifying the wording of what would be acceptable according to the code.



The code does not allow the T&P to discharge to the exterior when the water heater is inside, the T&P is required to discharge to the same room or space in which the water heater is located, and the discharge would need to be through an air gap to the receptor (or floor, or to wherever it is discharging).

I haven't heard of that before. Please help a neophyte out and show me a code section.

Mr. Bertrams,

The OP is in New York State, beyond the confines of New York (City).

It depends, would have to first establish which portion of the NYS code sets are applicable as per 19 NYCRR Part 1222.

PART 1222. PLUMBING CODE
-Section 1222.1 Plumbing code.
--(a) The 2010 PCNYS. Except as otherwise provided in section 1222.2, the erection, installation, alteration, repair, relocation, replacement, addition to, use or maintenance of plumbing systems, nonflammable medical gas systems, inhalation anesthetic systems, vacuum piping systems, non-medical oxygen systems, and sanitary and condensate vacuum collection systems, shall comply with the requirements of the publication entitled "Plumbing Code of New York State" (Publication Date: August 2010), published by International Code Council, Inc. Said publication (hereinafter referred to as the 2010 PCNYS) is incorporated herein by reference. Copies of the 2010 PCNYS may be obtained from the publisher at the following address:
International Code Council, Inc.
500 New Jersey Avenue, NW, 6th Floor
Washington, D.C. 20001
The 2010 PCNYS is available for public inspection and copying at:
New York State Department of State
99 Washington Ave.
Albany, NY 12231-0001

--(b) Referenced standards. Certain published standards are denoted in the 2010 PCNYS as incorporated by reference into 19 NYCRR Part 1222. Such standards are incorporated by reference into this Part 1222. Such standards are identified in the 2010 PCNYS, and the names and addresses of the publishers of such standards from which copies of such standards may be obtained are specified in the 2010 PCNYS. Such standards are available for public inspection and copying at the office of the New York State Department of State specified in subdivision (a) of this section.

--Section 1222.2. Exceptions.
---(a) The installation of fuel gas distribution and piping and equipment, fuel gas-fired water heaters and water heater ventilating systems shall comply with the requirements of the 2010 FGCNYS (the publication referred to in section 1224.1 (Fuel gas code) of Part 1224 of this Title).
---(b) Detached one- and two- family dwellings not more than three stories in height above grade with a separate means of egress, and their accessory structures, and multiple one-family dwellings (townhouses) not more than three stories in height above grade with a separate means of egress, and their accessory structures, shall comply with the requirements of the 2010 RCNYS (the publication referred to in section 1220.1 (Residential code) of Part 1220 of this Title).
---(c) Plumbing systems in existing buildings that are undergoing repairs, alterations, changes in occupancy or construction of additions shall be permitted to comply with the requirements of the 2010 EBCNYS (the publication referred to in section 1227.1 (Existing building code) of Part 1227 of this Title).

The discharge piping as installed is incorrect. It is technically "horizontal" in orientation, not properly supported, has a fitting/cemented section prior to discharge to indirect drainage, etc. and subjecting the potable system and the vessel to contamination below the flood rim of the set tub. The "elbow" cemented or chemically welded to adapter coupling reducing ID to less than full size TPRV discharge piping prior to drainage (not same thing). Not approved materials or method for NYS horizontal discharge. Onus upon you to prove otherwise, materials acceptance, size, schedule, application, etc. Spanned between two fixtures, horizontal relief valve discharge piping and fittings are neither secured nor supported properly. Indirect drainage piping not the same as discharge relief valve plumbing.

Common sense low tech non-code general safety issue user at laundry sink may be subjected to scalding injury.

AFAIK N. NYS does not and did not require siesmic strapping.

Additionally the vent connector is offset too close to the draft hood, insufficient rise prior to offset (horizontal or lateral pressure reduction). Questionable chimney connection, Uknwn thimble presence.

Appears to be unconditioned, uninsulated (beyond thermal envelope) Northern NYS basement (below 99% winter design temp), utilizing SW vent connector 3" to chimney.

Originally Posted by Jerry Peck

Not "in a stand pipe" but "into a standpipe through an air gap", just clarifying the wording of what would be acceptable according to the code.


The code does not allow the T&P to discharge to the exterior when the water heater is inside, the T&P is required to discharge to the same room or space in which the water heater is located, and the discharge would need to be through an air gap to the receptor (or floor, or to wherever it is discharging).

Originally Posted by David Bertrams

I haven't heard of that before. Please help a neophyte out and show me a code section.

David,

First to the IPC/IRC and codes based on the IPC/IRC (such as the New York State codes): (bold and underlining are mine)
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.
- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.
- - 6. Discharge in a manner that does not cause personal injury or structural damage.
- - 7. Discharge to a termination point that is readily observable by the building occupants.
- - 8. Not be trapped.
- - 9. Be installed to flow by gravity.
- - 10. Not terminate more than 6 inches (152 mm) above
the floor or waste receptor.
- - 11. Not have a threaded connection at the end of the piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

This is from the NYS RC
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature- relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.
- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.
- - 6. Discharge in a manner that does not cause personal injury or structural damage.
- - 7. Discharge to a termination point that is readily observable by the building occupants.
- - 8. Not be trapped.
- - 9. Be installed to flow by gravity.
- - 10. Not terminate more than 6 inches (152 mm) above the floor or waste receptor.
- - 11. Not have a threaded connection at the end of the piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

Codes differ from area to area, but all require over temperature protection to shut off these devices. TPR valves are required to terminate to safe locations, most outside period. Some allow open receptors as mop sinks, but air gaps are always required.

It is improper and unsafe.

Originally Posted by Jerry Peck

David,

First to the IPC/IRC and codes based on the IPC/IRC (such as the New York State codes): (bold and underlining are mine)
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.
- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.
- - 6. Discharge in a manner that does not cause personal injury or structural damage.
- - 7. Discharge to a termination point that is readily observable by the building occupants.
- - 8. Not be trapped.
- - 9. Be installed to flow by gravity.
- - 10. Not terminate more than 6 inches (152 mm) above
the floor or waste receptor.
- - 11. Not have a threaded connection at the end of the piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

This is from the NYS RC
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature- relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.
- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.
- - 6. Discharge in a manner that does not cause personal injury or structural damage.
- - 7. Discharge to a termination point that is readily observable by the building occupants.
- - 8. Not be trapped.
- - 9. Be installed to flow by gravity.
- - 10. Not terminate more than 6 inches (152 mm) above the floor or waste receptor.
- - 11. Not have a threaded connection at the end of the piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

You stated: "The code does not allow the T&P to discharge to the exterior when the water heater is inside, the T&P is required to discharge to the same room or space in which the water heater is located, and the discharge would need to be through an air gap to the receptor (or floor, or to wherever it is discharging)."

What you have underlined in #2 above is that if there is an air gap involved [i.e. the T&P drains to an indirect waste receptor, or to the outside in an area that experiences freezing] the air gap must be in the same room as the water heater. #5 makes it clear that a water heater located inside is allowed to discharge to the exterior, no air gap required unless the property is located in an area that experiences freezing.

Originally Posted by Jerry Peck

David,

First to the IPC/IRC and codes based on the IPC/IRC (such as the New York State codes): (bold and underlining are mine)
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.
- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.

This is from the NYS RC
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature- relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.
- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.

(underlining and bold are mine)

Originally Posted by David Bertrams

What you have underlined in #2 above is that if there is an air gap involved ...

Quite incorrect, David, what the code says is this:
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature- relief valve or combination valve shall: 2. Discharge through an air gap located in the same room as the water heater.

There is no "IF" in there.

The discharge SHALL DISCHARGE THROUGH AN AIR GAP LOCATED in the same room as the water heater.

#5 makes it clear that a water heater located inside is allowed to discharge to the exterior, no air gap required unless the property is located in an area that experiences freezing.

Quite incorrect again.

#5 is the pipe AFTER the air gap in #2.

"IF" the discharge pipe after the REQUIRED air gap discharges to the exterior, then it shall be protected from freezing.

There is no shall meet 'one of the following' in there, that list is all inclusive, the discharge SHALL meet 1., 2., etc., through 13.

Originally Posted by Jerry Peck

(underlining and bold are mine)


Quite incorrect, David, what the code says is this:
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature- relief valve or combination valve shall: 2. Discharge through an air gap located in the same room as the water heater.

There is no "IF" in there.

The discharge SHALL DISCHARGE THROUGH AN AIR GAP LOCATED in the same room as the water heater.



Quite incorrect again.

#5 is the pipe AFTER the air gap in #2.

"IF" the discharge pipe after the REQUIRED air gap discharges to the exterior, then it shall be protected from freezing.

There is no shall meet 'one of the following' in there, that list is all inclusive, the discharge SHALL meet 1., 2., etc., through 13.

I give up. I should have known better than to question the master. Anybody who reads this thread, please know that a T&P is not allowed to terminate on the exterior if the water heater is located indoors and all T&P shall have an air gap in the same room as the water heater, without exception.
That should put an end to the discussion. I agree with you 100%.

Mr. B.

I can opine with some certainty that all surface areas uncovered and unheated outdoors in NYS are indeed subject to freezing at some point during the year, "global warming" not withstanding.

However, the pictured laundry sink/tub pictured is indoors, although likely in a basement which may or may not be heated or subject to freezing in the most extreme of winter conditions, it does indeed appear to be "indoors", so I really don't follow where you and Peck are heading off topic or why.

The relief valve discharge terminates within the confines of the laundry tub/sink. which in this case is a receptor. From there on the products of "discharge" have become 'drainage".

The primary "problem" regarding health and safety was identified by SP above. The potential for contamination is evident - as the "receptor" is not indirect - and is a public health hazard/plumbing hazard - as would be a direct discharge to the outdoors subject to contamination via flood, offal, bird, rodent excrement, bugs, animals licking, insect drinking, or contacting drips, flood, etc.

Hi, ALL &

"Up here" (B.C., Canada) it's either a METAL TPR discharge or plastic - so long as is labelled /rated for at least 99 C. temp. (just short of boiling point)...

CHEERS !

Here in San Diego, new and old construction, the water heaters are often in the garage and the TPR pipe terminates outside. I don't like that type of installation, and tell my Clients that I don't, but ultimately the State of California considers its licensed plumbers and building/code enforcement offiicials to be much more knowledgeable than a lowly California home inspector since we have no licensing in this state, and those plumbers and enforcement officials have no problem with terminating the pipe outside. Even when the water heater happens to be in the house, pipes still terminate outside.

Yet another to add to the mix. The 'discharge' end was sweated to 3/4" copper which disappeared into the wall behind the heater and above the height of the TPR valve.

ip

I've seen leaky TPR valves "fixed" this way.

i think it has to go straight down & 4-6" from floor. I've always used pvc

max. service temp. for pvc 140f, learned somethin new today

One of the reasons for such a variety of answers is the diversity of codes and applications of them across America.
Here in California, we go by the CPC, with some latitude noted as to termination location:

608.5 Relief valves located inside a building shall be provided
with a drain, not smaller than the relief valve outlet, of galvanized
steel, hard-drawn copper piping and fittings, CPVC or
listed relief valve drain tube with fittings that will not reduce
the internal bore of the pipe or tubing (straight lengths as opposed
to coils) and shall extend from the valve to the outside of
the building, with the end of the pipe not more than two (2)
feet (610 mm) nor less than six (6) inches (152 mm) above
ground or the flood level of the area receiving the discharge
and pointing downward. Such drains shall be permitted to terminate
at other approved locations. Relief valve drains shall
not terminate in a buildings crawl space. No part of such drain
pipe shall be trapped or subject to freezing. The terminal end of
the drain pipe shall not be threaded.

Ian, please note the flex SUPPLY line used in your picture is not listed for that application, I believe because it's minimum inside diameter is less that the diameter at the valve. Not allowed.

Russel, it seems it's up to the AHJ where these things can terminate, but I mostly see them outside as well. Why do you prefer them not to terminate outside?

Gary
I know the flex tubing is not approved for this application, let alone joining two lengths together. The whole discharge is incorrect. Furthermore, I never was able to locate the discharge point, inside or outside the house.
I recommended having a licensed and qualified plumber replace and install pursuant to code requirements. Now where the customer goes from here is their choice. The property is a short sale and the seller nor the lender are likely to make good.

I posted the pic. to demonstrate yet another 'variety' of plumbing fixes. Incidentally, this 'fix' was made by one of the Big Box company, so-called Water Heater installers.

ip

Some of you are getting hung up on missing application of additional qualifiers and areas of the code (plumbing, contamination, protecting water supply) distinctions with a difference.

General list of requirements of a relief discharge apply to all such discharges. Not ALL discharges are SUPPLIED by otherwise UNPROTECTED Potable SUPPLY.

For example isolated from the potable system/supply would be for example similar storage type water heaters installed to supply hydronic heat, boilers installed for same, ETC.

Discharge of temperatures at/above 140 F are SPECIAL wastes, and A HAZARD. Discharge at higher PRESSURES are also SPECIAL wastes, in how they are handled. Relief discharge from POTABLE supplies, potable vessles, the potable SYSTEM must be protected from CONTAMINATION, as must the SUPPLY to the potable system (even when the potable supply to the system loses pressure.

Water Heater and the potable supply is unprotected as pictured in original photo, as is its storage tank and the supply and outlet, the discharge and the relief valve may NOT have a "check" (which could fail, close, and be a hazard) - the relief valve is NOT a PROTECTING valve, check valve, backflow preventer, etc. Relief valves may open partially, not close fully, etc.

Therefore the DISCHARGE (not the DRAINAGE, which comes AFTER) is required to meet the requirements of potable supply, AND Temperature AT pressure (not temperature at LESS than full pressure of the DISCHARGE) and PRESSURE AT TEMPERATURE of the DISCHARGE parameters of the RELIEF VALVE full Range and tolerance.

The discharge TERMINATES In the OP's photo WITHIN the Tub, BELOW the FLOOD RIM of the Fixture (laundry tub) acting as a RECEPTOR for the DISCHARGE AND the Discharge Pipe IS IN CONTACT with the Receptor.

The DRAINAGE , which comes AFTER an air gap, Receptor, etc. IS LIMITED to Temperatures below 140 F, and MOST materials at Higher temperatures as configured are LIMITED as to PRESSURE co-efficients far less than 150 PSI.

T&P Relief Valves' on Residential Water Heaters installed upon the potable water supply system, DISCHARGE may be BOTH 210 degrees F AND 150 PSI; far exceeding limitations for the products of and system for "regular" DRAINAGE, which is why it is DISCHARGE and what is being DISCHARGED is "SPECIAL" - UNLESS and/or UNTIL the PRODUCTS OF DISCHARGE (special wastes) is/are "converted" to the parameters of "regular" DRAINAGE.

If the "system" and products of discharge are for example chemically treated - may still not be "regular drainage" and may require additional SPECIAL handling (anti-freeze, anti-corrosives, chemical additives, contaminates, other special considerations).

Here in Georgia, most I have seen has the discharge terminating outdoors, pipe buried inside walls.

Also, I like CPVC pipe. Installed it in my parents house built in 1972 and never has had a leak, except a couple transitions using copper pipe all corroded and leaked. Much of the water here can corrod copper piping and casue copper sulfate poisoning, My grandfather almost died of it, we had to yank out all the copper and replace with CPVC in his house back in the late 70's.
I will never use copper in my house, plastic is the only way to go, I prefer CPVC, PEX is easy to install if have all the tools and do it right, but I have had bad experiences with earlier flexible piping solutions, PEX seems to be holding up but only more time will tell. But I like CPVC the most for now.

Originally Posted by Mike Clarke

Here in Georgia, most I have seen has the discharge terminating outdoors, pipe buried inside walls.

Also, I like CPVC pipe. Installed it in my parents house built in 1972 and never has had a leak, except a couple transitions using copper pipe all corroded and leaked. Much of the water here can corrod copper piping and casue copper sulfate poisoning, My grandfather almost died of it, we had to yank out all the copper and replace with CPVC in his house back in the late 70's.
I will never use copper in my house, plastic is the only way to go, I prefer CPVC, PEX is easy to install if have all the tools and do it right, but I have had bad experiences with earlier flexible piping solutions, PEX seems to be holding up but only more time will tell. But I like CPVC the most for now.

CPVC has many problems as you will see, you mentioned some joints fail, also your hot water will make the piping brittle in time, exposure to sunlight will do that too. It's not code approved within the dwelling in California. There are possible unknown health issues with the glue. Make sure it's tightly strapped, water hammer can blow out fittings. I wouldn't chance it.

[quote=Tom Thompson;167263]CPVC has many problems as you will see, you mentioned some joints fail, also your hot water will make the piping brittle in time, exposure to sunlight will do that too. It's not code approved within the dwelling in California.

tom,
it is code approved in california. see table 6-4 of the california plumbing code