Thread: TPR Indirect Waste Receptor Material

Does anyone know if PVC can be used for a TRP drain? Is there a list of approved materials for the drain?

Thanks for the help!

Similar Threads:

• Valley material
• Waste Connection
• Indirect waste lines...
• Primary drain line material
• Draft hoods , combustible material

Originally Posted by boiler qwerty

Does anyone know if PVC can be used for a TRP drain?

PVC is not allowed for that use.

Is there a list of approved materials for the drain?

While the code section number may change from edition to edition, the 2006 IRC number is: Table P2904.5 Water Distribution Pipe.

If it is on that list, then it is suitable for hot water.

PVC is not on that list, PVC is listed in Table P2904.4 Water Service Pipe and is suitable for cold water service to, but not into, the structure.

Often times the TPR discharge pipe is inappropriately referred to as a drain pipe.
It is not a drain pipe, it is the discharge pipe. The discharge pipe empties (most often) into the "Indirect Waste Receptor".
Your question is about the indirect waste receptor

I believe in the picture it is referring to a indirect waste receptor that being said it could be part of the drainage system that would then allow PVC.

RECEPTOR. A fixture or device that receives the discharge from indirect waste pipes.

INDIRECT WASTE PIPE. A waste pipe that discharges into the drainage system through an air gap into a trap, fixture or receptor.

Originally Posted by paul hardy

I believe in the picture it is referring to a indirect waste receptor that being said it could be part of the drainage system that would then allow PVC.

RECEPTOR. A fixture or device that receives the discharge from indirect waste pipes.

INDIRECT WASTE PIPE. A waste pipe that discharges into the drainage system through an air gap into a trap, fixture or receptor.

P2801.5.1 Pan size and drain. The pan shall be not less
than 11/2 inches (38 mm) deep and shall be of sufficient size
and shape to receive all dripping or condensate from the
tank or water heater. The pan shall be drained by an indirect
waste pipe having a minimum diameter of 3/4 inch (19 mm).
Piping for safety pan drains shall be of those materials listed
in Table P2904.5.

Any material which is approved for DRAINAGE/WASTE at hot water temperatures is permissible. It does not require potable or supply/distribution water approval critera and does not have to be listed on the table indicated by the first repsponder.


The OP has not indicated TPRV DISCHARGE in demarking diagram, but DRAINAGE.

After free-air, air-gap, the former TPRV discharge "special waste" has been "converted" to DRAINAGE. If PVC is legal to use for same and exposed, in your jurisdiction, for drainage piping, and provisions sufficient for expansion & contraction, it may be employed as you indicate

.

Ignoring other subject issues with notations/diagram.

Originally Posted by H.G. Watson, Sr.

Any material which is approved for DRAINAGE/WASTE at hot water temperatures is permissible. It does not require potable or supply/distribution water approval critera and does not have to be listed on the table indicated by the first repsponder.

watson,

Do you not know how to read?

Just curious why you would blatantly state something so incorrect when the correct information has already been posted BY TWO OTHER PEOPLE ...

The code allows for the discharge piping to an indirect waste receptor that indirect waste receptor is covered in chaper 8 indirect/special waste that allows for high tempature and even steam pipes to discharge into a waste receptor connected to the drainage system it also allows materials used in chaper 7 sanitary drainage that includes PVC.

Chapter 8 - Indirect/special Waste

803.1 Wastewater temperature.

Steam pipes shall not connect to any part of a drainage or plumbing system and water above 140°F (60°C) shall not be discharged into any part of a drainage system. Such pipes shall discharge into an indirect waste receptor connected to the drainage system.

804.1 General.

The materials and methods utilized for the construction and installation of indirect waste pipes and systems shall comply with the applicable provisions of Chapter 7.

Just to clarify, my question was referring to the material for the drainage of the TPRV discharge pipe. I know that the TPRV discharge pipe has to follow P2803.6.1 (IRC 2006). In my case, the TPRV discharge pipe will be copper. Also, the drain pan discharge pipe will be copper.

Looking at my attached drawing, I wanted to know the approved material for the piping that is labeled "Indirect Waste Receptor".

After reading the various code book sections you all have recommended, it seems that PVC would be an acceptable material for use as an indirect waste receptor. But PVC is NOT acceptable for the TPRV and drain pan discharge piping.

Am I correct in my conclusion? Any thoughts?

Originally Posted by boiler qwerty

Just to clarify, my question was referring to the material for the drainage of the TPRV discharge pipe. I know that the TPRV discharge pipe has to follow P2803.6.1 (IRC 2006). In my case, the TPRV discharge pipe will be copper. Also, the drain pan discharge pipe will be copper.

Looking at my attached drawing, I wanted to know the approved material for the piping that is labeled "Indirect Waste Receptor".

For the same reasons that the water heater pan drain line needs to be of material specified in Table P2904.5, and for the same reasons that the water heater T&P relief valve discharge piping needs to be of material specified in Table P2904.5, that indirect waste receptor also needs to be of material specified in Table 2904.5.

The reason that the water heater drain pan drain needs to be of material specified in Table P2904.5 is that is it a common (albeit a poor) practice is to discharge the T&P relief valve discharge piping into the water heater drain pan with the hot water discharging into the drain pan and out the drain piping. Research showed that the drain piping being installed was PVC and the PVC drain piping was failing under the high temperature conditions of the water, thus the code was changed to acknowledge that installation practice and to clarify the types of materials which would be suitable for the drain line - any of the materials in Table P2904.5 Distribution Pipe as those material are designed and intended to withstand the affect of that hot water.

After reading the various code book sections you all have recommended, it seems that PVC would be an acceptable material for use as an indirect waste receptor. But PVC is NOT acceptable for the TPRV and drain pan discharge piping.

I cannot find where it says that PVC would be an acceptable material for that indirect waster receptor, would you point me toward that code section? Thanks.

Originally Posted by Jerry Peck

I cannot find where it says that PVC would be an acceptable material for that indirect waster receptor, would you point me toward that code section? Thanks.

I was referring to the code sections that Paul Hardy was talking about; Chapters 7 and 8 from UPC 2009. But, after re-reading those chapters, I don't know if it justifies using PVC for the situation I have in my drawing.

I'll look more closely at this some more, and I'll comment again sometime tonight or tomorrow. Maybe I'm confused about the definition of an indirect waste receptor.

P. Hardy set you straight in Post #8, and your written first part of your response #9 okay, the new drawing "plan" attached to #9 is not.

Originally Posted by boiler qwerty

I was referring to the code sections that Paul Hardy was talking about; Chapters 7 and 8 from UPC 2009. But, after re-reading those chapters, I don't know if it justifies using PVC for the situation I have in my drawing.

I'll look more closely at this some more, and I'll comment again sometime tonight or tomorrow. Maybe I'm confused about the definition of an indirect waste receptor.

Not all indirect waste receptors are created equal ... just as not all indirect waste receptors are used equally -- you need to use an indirect waster receptor constructed from materials compatible with the use of the indirect waster receptor. PVC is not a "one size fits all" material.

Hmmm ... maybe PVC is a "one size fits all" material in that if you get it hot enough it may well fit anything you drape it over ...

Originally Posted by Jerry Peck

watson,

Do you not know how to read?

Just curious why you would blatantly state something so incorrect when the correct information has already been posted BY TWO OTHER PEOPLE ...

Yep, and do. Do You?

The title of the discussion IS: TPR Indirect Waste Receptor Material.

First post photo clearly indicates the DRAINAGE not the discharge.

Poster has indicated his location profile specific locale in IN.

Btw safe pans for storage type water heaters may be
"other pans approved for such use" (504.7)

OP, PH's references were IPC not, UPC.

Originally Posted by H.G. Watson, Sr.

Yep, and do. Do You?

Are you SURE you do?

The title of the discussion IS: TPR Indirect Waste Receptor Material.

First post photo clearly indicates the DRAINAGE not the discharge.

The materials used for the DRAIN LINE ... ARE DEPENDENT ... on what is being DISCHARGED into the indirect waste receptor.

As the OP (Original Poster) stated in the OP (Original Post) that DISCHARGE is from a T&P relief valve and thus the material of the indirect waste receptor MUST BE SUITABLE FOR THAT DISCHARGE.

The OP (Original Poster) asked about PVC, and PVC ... IS NOT ... suitable for that discharge because of the hot water or steam which would be discharging from the discharge opening at the end of the discharge pipe and into the indirect waster receptor and into its drain piping.

As I stated before, the material of the indirect waste receptor must be compatible with what is being discharged into it.

Would you use a thin sheet metal indirect waste receptor and galvanized piping if caustic chemicals were being discharged into the indirect waster receptor? Hopefully you would have the sense to use materials which were compatible with the substance being discharged.

Sigh...

Nothiing is being "discharged" into it. The terminus of the discharge is the air gap. The receptor is receiving through free air: waste, in this case clear hot water waste from a potable source. The transition (or transformation) to drainage via air occurs at the outlet of the discharge.

Originally Posted by H.G. Watson, Sr.

Sigh...

Nothiing is being "discharged" into it. The terminus of the discharge is the air gap.

Sigh ... Sigh ...

You say "Nothiing is being "discharged" into it."???

Please help me understand how water is exiting the discharge opening of the T&P relief valve discharge pipe ... and the water is not being discharged into the indirect waster receptor ... and the water is not going anyplace else either ... the water is what - just disappearing into the air?

watson, that is one of your more sillier comments ... not the silliest comment you have concocted to try to explain why you being wrong is you not being wrong but you being right ...

The receptor is receiving through free air: waste, in this case clear hot water waste from a potable source.

So you are now saying that the indirect waste receptor *IS* receiving the water being discharged through the T&P relief valve discharge pipe?

watson, make up your mind - either the indirect waste receptor *IS* ... or *IS NOT* ... but it cannot be *BOTH* ... receiving the water being discharged through the T&P relief valve discharge pipe. If you say it *IS NOT*, then explain where the water is going. If you say it *IS*, then the water is discharging into the indirect waste receptor and thus the indirect waster receptor is receiving that discharge.

This is your opportunity to make one of your 300 page posts trying to support your statements above.

The transition (or transformation) to drainage via air occurs at the outlet of the discharge.

And the water is still "discharged" from the discharge pipe opening and the indirect waster receptor is still receiving that "discharge".

Which brings us back full-circle to your statement "Nothiing is being "discharged" into it."

Thanks for all the comments and input. I'm still looking around in the various code books for a clear answer. I did come across IPC 701.7: "Waste water where discharged into the building drainage system shall be at a temperature not greater than 140F. Where higher temperatures exist, approved cooling methods shall be provided." This statement seems to apply to the situation where the water being discharged from the TPRV would be entering the building drainage system. But now I need to find what the "approved cooling methods" are.

It makes sense that the indirect waste receptor for the TPRV discharge piping must withstand high temperatures. But if you look at IRC Table P2904.5, there is a limited amount of materials to choose from.

So, if I have a water heater that discharges hot water into an indirect waste receptor, and that indirect waste receptor is a floor drain, that floor drain and the floor drain piping must be made from materials listed in Table P2904.5? When am I allowed to transition from the high-temperature material to a common material? To me it seems that PVC or ABS are typical sewage piping.

Originally Posted by boiler qwerty

Thanks for all the comments and input. I'm still looking around in the various code books for a clear answer. I did come across IPC 701.7: "Waste water where discharged into the building drainage system shall be at a temperature not greater than 140F. Where higher temperatures exist, approved cooling methods shall be provided." This statement seems to apply to the situation where the water being discharged from the TPRV would be entering the building drainage system. But now I need to find what the "approved cooling methods" are.

It makes sense that the indirect waste receptor for the TPRV discharge piping must withstand high temperatures. But if you look at IRC Table P2904.5, there is a limited amount of materials to choose from.

So, if I have a water heater that discharges hot water into an indirect waste receptor, and that indirect waste receptor is a floor drain, that floor drain and the floor drain piping must be made from materials listed in Table P2904.5? When am I allowed to transition from the high-temperature material to a common material? To me it seems that PVC or ABS are typical sewage piping.

From the 2006 IRC:
- APPROVED. Acceptable to the building official.

From the 2006 IPC:
- APPROVED. Acceptable to the code official or other authority having jurisdiction.

The above are one and the same as the building official is the AHJ.

I also suspect that a PVC drain which is cast in place in a concrete slab has adequate cooling properties to keep the PVC from deforming from the higher water temperatures, and that the PVC drain piping which then goes down into earth also has that same adequate cooling property.

as an ahj i would find the pvc acceptable for this situation. One for watson.

Sadly some seem hung up on basic definitions and the various "parts of speach".


We have verbs and nouns.

the indirect-ness of interconnection is what determines where and when the "discharge (verb - action)" 'event' takes place - and when the discharge (noun - the "thing" itself) has been "discharged" (i.e it has "escaped" the confines of its prior restriction) and in this case no longer "charged" under excessive pressure - at atmospheric (free air).

To discharge in plumbing is to be directly transmitted from origin and requires a direct contained connection to its (the "thing" which is being discharged) origin.. Be it the "discharge" from a fixture, a pump, a valve, etc.

Once the tubing or pipe from the tprv has been terminated to free air and dually befitting and protecting air gap (both airgap, distribution and airgap, drainage) it has been fully exposed to atmosphere. Pressure equalization takes place, energy release is also afforded. what therefore comes forth from this opening HAS BEEN DISCHARGED. What is being received by and collected/directed from the INDIRECT WASTE RECEPTOR is de-pressurized via free-air-fall drainage.

There is no direct connection beyond the end (opening to free air - required "air gap") of the TPRV tube or pipe from its source, therefore no "discharge" is taking place into the indirect waste receptor. The plumbing (piping, tubing) from the TPRV valve outlet is indirect waste piping. That "end" of that tube or pipe is the POINT of "discharge" - as free air unrestrained is encountered - the discharge takes place - the transmission event occurs - what results beyond the point of discharge (the pipe or tube "end" or opening) is no longer discharge! it was discharge before it encountered that gravity opening, but once it "hits" that "free air" it is now dischargED (the resulting product and chacteristics of having been dischrged). When the valve closes what remains in the tube or pipe is furthermore no longer being "discharged" therefore it too is drainage.

The prohibition is 140F temp under pressure being DISCHARGED and that means DIRECT CONNECTION from the discharge pathway's origin to the drainage system.

There is no such (discharge to the drainage system) when the multiply prescribed "free air" air gap is employed.

The reason pressure or temperature & pressure valves must "discharge" to free air - eventually.

The inside of the tank is at higher than atmospheric pressure with the tprv closed. With the valve open - and the fluid at the end of the trpv discharge pipe or tube - entrance of atmospheric air, and release of pressure, pressure within is equalized and at the outlet of the valve piping is completely equalized. Ennergy released is dramatic, absolute temperature of the water reduced, and following its escape (discharge) from the confines of its directing tube (at opening) the resulting is drainage.

Originally Posted by H.G. Watson, Sr.

Sadly some seem hung up on basic definitions and the various "parts of speach".

Agreed, and they are also hung up on them being right when they are not.

Guess where this came from:
- RECEPTOR. A fixture or device that receives the discharge from indirect waste pipes.

- P2706.3 Prohibited waste receptors. Plumbing fixtures that are used for domestic or culinary purposes shall not be used to receive the discharge of indirect waste piping.
- - Exceptions:
- - - 1. A kitchen sink trap is acceptable for use as a receptor for a dishwasher.
- - - 2. A laundry tray is acceptable for use as a receptor for a
clothes washing machine.

- 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.

- EMERGENCY FLOOR DRAIN. A floor drain that does not receive the discharge of any drain or indirect waste pipe, and that protects against damage from accidental spills, fixture overflows and leakage.

- INDIRECT WASTE PIPE. A waste pipe that does not connect directly with the drainage system, but that discharges into the drainage system through an air break or air gap into a trap, fixture, receptor or interceptor.

- 709.4 Values for indirect waste receptor. The drainage fixture unit load of an indirect waste receptor receiving the discharge of indirectly connected fixtures shall be the sum of the drainage fixture unit values of the fixtures that discharge to the receptor, but not less than the drainage fixture unit value given for the indirect waste receptor in Table 709.1 or 709.2.

The above references are all referring to indirect waste receptors, and those indirect waste receptors are receiving the discharge from ... oh, wait, according to you they are not receiving the discharge from ... even though the code says they are.

The piping from the TPRV is indirect waste piping.There is a break.The receptor is receiving indirect waste NOT discharge. The receptor collects drainage itself. The receptor itself itself may "discharge" directly to the drainage or as indicated in the original (first post) diagram - it may be be yet another indirect waste pathway, "discharge" directed to yet another "outlet".However once the containment pathway is broken (air gap, indirect) it is has been "discharged" and the products of that discharging event are indeed discharge. What is being collected is drainge. The products of that having been previously discharged INDIRECT are drainage - which may be "drained" or further collected, intercepted, treated, and further eventually "discharged" yet again, or NOT. The indirect outlet of prescribed conditions is the intital "converting" event in the original PERTAINING example question of the OP.The dishwasher, pumped product, air-gap example by another is entirely inapplicable to the TPRV discharge pressure/temperature and potable system to DRAINAGE system discussion. The IPC further addresses the means for temperature reduction post pressure equaliztion for boilers (steam and hot water) and water heaters of potable clear water waste from the PRV, TRV or TPRV discharge. Neither the unammended IRC nor the unmmended IPC require what Peck asserts for the DRAINAGE or discharge materials which follow the initial INDIRECT WASTE RECEPTOR. The OP has not indicated a "super-size" storage-type residential water heater.

Originally Posted by Jerry Peck

Agreed, and they are also hung up on them being right when they are not.

Guess where this came from:
- RECEPTOR. A fixture or device that receives the discharge from indirect waste pipes.

- P2706.3 Prohibited waste receptors. Plumbing fixtures that are used for domestic or culinary purposes shall not be used to receive the discharge of indirect waste piping.
- - Exceptions:
- - - 1. A kitchen sink trap is acceptable for use as a receptor for a dishwasher.
- - - 2. A laundry tray is acceptable for use as a receptor for a
clothes washing machine.

- 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.

- EMERGENCY FLOOR DRAIN. A floor drain that does not receive the discharge of any drain or indirect waste pipe, and that protects against damage from accidental spills, fixture overflows and leakage.

- INDIRECT WASTE PIPE. A waste pipe that does not connect directly with the drainage system, but that discharges into the drainage system through an air break or air gap into a trap, fixture, receptor or interceptor.

- 709.4 Values for indirect waste receptor. The drainage fixture unit load of an indirect waste receptor receiving the discharge of indirectly connected fixtures shall be the sum of the drainage fixture unit values of the fixtures that discharge to the receptor, but not less than the drainage fixture unit value given for the indirect waste receptor in Table 709.1 or 709.2.

The above references are all referring to indirect waste receptors, and those indirect waste receptors are receiving the discharge from ... oh, wait, according to you they are not receiving the discharge from ... even though the code says they are.

You've tripped yourself up there peck: you trip from the start, and especially at the end.

A receptor, an INDIRECT receptor, an interceptor.

Distinction - qualified adjective - INDIRECT.

Distinction - INDIRECT waste pipe - qualified term - containing the qualifiying adjective - INDIRECT.

Drainage Fixture Units. I suggest you familiarize yourself with just what that means peck, and to WHAT is being referred to.

Not all "floor drains" are "emergency floor drains", yep, which of course is just one of your many "glitches" - as is your glitch as to the distinction between an interceptor and a receptor and in indirect receptor.

The OP drawing does not have a discharge TO a mere "RECEPTOR" it is discharge TO a qualiying, prescribed FREE "air gap", DRAINS via GRAVITY through FREE AIR, UNRESTRAINED and UNDIRECTED by other than gravity, at ATMOSPHERIC PRESSURE and FALLS from above the flood level rim (prescribed distance) and DRAINS to an INDIRECT RECEPTOR - the air gap between the discharge point and the flood level rim of the indirect waste receptor must meet BOTH the air gap, distribution AND the air gap, drainage requirements. The discharge POINT is above - in the prescribed arrangement provided by the unammended CODE, and which is being discussed (and clearly is over your head).

It does not DISCHARGE TO A RECEPTOR, it discharges TO THE FREE AIR, fluid clear water waste FALLS (gravity) via the prescribed free air, unrestrained, and via prescribed distance, and falls into the INDIRECT receptor. What "falls" is depressurized, and has experienced a release of energy.

Hey watson, you need to learn to read and understand what you read. An indirect waster receptor receives the discharge which is discharged from the indirect waste pipe.

That discharge does not magically and mysteriously change as it crosses 2" of air.

Personally, I think this is picking fly poop out of black pepper. While you guys slug it out over this issue its the venting that is going to kill or injure the occupants.

I don't know if this has been tested but hot water discharged through an air gap into a pipe with ambient air entrainment should not get as hot as one used as 'piping' in full and continuous contact such as a hot water pipe that does not have all that cooling air.

I'd find something else to worry about like why is the TPR discharging in the first place and how is the homeowner to know and who trained them to recognize such discharge is a call for action. Even if they see it happening, few call for service.

yes of course its been tested.

and yes of course depressuriztion occurs, and yes of course energy is released, and yes of course temperature is reduced.

And of course why one may even indirect waste pipe hot water boiler discharge indirectly via free air to fall to indirect receptor and evenually to drainage system, in the same way without requiring an interceptor or conversion sump.

The physical laws don't change just because J.P. doesn't understand them, or confuses the use of a verb with a noun, and hasn't the understanding of the systems being discussed, therefore can't follow the specific distinctions between pressurized transported discharge, when it is no longer same, at the point of discharge and equalization, and the result of same.

Originally Posted by H.G. Watson, Sr.

The physical laws don't change just because J.P. doesn't understand them, or confuses the use of a verb with a noun, and hasn't the understanding of the systems being discussed, therefore can't follow the specific distinctions between pressurized transported discharge, when it is no longer same, at the point of discharge and equalization, and the result of same.

I will continue to read and understand what the codes says without regard to what watson wants it so say. The code says that the water heater T&P may discharge to an indirect waste, the codes sections I posted related to that - and the water being discharged from the indirect waste pipe (which is what the T&P relief valve discharge pipe becomes) when the T&P relief valve opens is the same discharge which is going into the indirect waste receptor.

I will leave this with watson to continue to try to find a way to turn his incorrect statements about it into something that he believes, and that he hopes some of you will believe.