Opinions on T&P discharge changes.

[Joshua Hardesty]

These aren't new changes, but a while ago we used to be able to run the T&P from a heater down & out of a house, or if it was in the crawlspace, through the side of the house and into the lawn.

Now, the T&P *must* discharge into an indirect waste in the same room as the heater, and code inspectors (in my area at least) consider the crawlspace to be a room, and so I have to put an indirect drain in there too. Now my question is, how do you vermin-proof such things?

We're supposed to fill the gap we have to cut around a tub drain on the first floor, but then the code tells us to run a direct access hole for anything that wants to crawl up a pipe from the outside of the house to the heater?

[Matt Vozzella]

Where are you located? And could you post the source and the code?

I'm not doubting you be requiring indirect connection in the same room as the water heater seems to be an undue burden on the home owner. To make it "maintenance free" the homeowner would also have to run a trap primer. Again, this seems to be a burden to anyone in the area of concern. Also, I believe having the T&P discharge outside would be safer. A T&P that trips as intended could be dangerous if anyone was there at the time.

Sorry, not an answer to your question, my curiousity is peaked.

[Jerry McCarthy]

Don't know where you're located Joshua, but for California Inspectors this is what the story is code wise.
California Plumbing Code – 2007:
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 (610mm) nor less than six (6) inches (152 mm) above the ground or the flood level of the area receiving the discharge and pointing downward. Such drains may terminate at other approved locations. Relief valve drains shall not terminate in a building’s 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.

I highlighted the significant change for 2007.

[Jerry Peck]

From the IRC. (underlining and bold 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. through 13. not posted as 2. is relevant to the discussion.

From the IPC.
- 504.6 Requirements for discharge piping.The discharge

piping serving a pressure relief valve, temperature relief valve
or combination thereof 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. through 13. not posted as 2. is relevant to the discussion.

[Matt Vozzella]

- 504.6 Requirements for discharge piping.The discharge

piping serving a pressure relief valve, temperature relief valve
or combination thereof 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. through 13. not posted as 2. is relevant to the discussion.




Florida Plumbing Code 2007
504.6 Requirements for discharge piping. The discharge piping serving a pressure relief valve, temperature relief valve or combination thereof shall:


1. Not relevant to this conversation.
2.Discharge through an air gap located in the same room as the water heater.
3,4. Not relevant to this conversation.
5. Discharge to the floor, to the water heater pan, 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.

Just curious, what does 5 say in the IPC, I don't have access.

[Jerry Peck]

Just curious, what does 5 say in the IPC, I don't have access.


Matt,

The IPC and the IRC are the same, I will post the entire section along with 1 through 13 (from the 2006).

- 504.6 Requirements for discharge piping. The discharge piping serving a pressure relief valve, temperature relief valve or combination thereof 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 so as 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 such piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section 605.4 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

[Matt Vozzella]

Hmmmm....5 seems to contradict 2.

- - 2. Discharge through an air gap located in the same room as the water heater.


- - 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.


Would 2 just be a provision for areas subject to freezing?

[Tim Saunders]

This is acceptable for water heaters in conditioned areas
The pan drain is connected to the sewer, the T&P extension drains the belled PVC which discharges onto the garage slab

Hope this helps

Tim

[Jerry Peck]

Hmmmm....5 seems to contradict 2.

Matt,

There is no contradiction.

- - 2. Discharge through an air gap located in the same room as the water heater.

2 says The T&P relief valve MUST (is required to) discharge to an air gap within the same room as the water heater.


- - 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.

5 says that the discharge from the air gap: MAY discharge to: a) the floor, b) an indirect waste receptor or, c) to the outdoors. The only way to get to the outdoors from an indoor water heater is to discharge to an indirect waste receptor which drains to the outdoors.

Read that list this way - the first items take precedence over later items.

#1 thing to do/not do. Not be directly connected to the drainage system.
#2 thing to do/not do. Discharge through an air gap located in the same room as the water heater.
#3 thing to do/not do. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
#4 thing to do/not do. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
#5 thing to do/not do. ...

[Jerry Peck]

This is acceptable for water heaters in conditioned areas
The pan drain is connected to the sewer, the T&P extension drains the belled PVC which discharges onto the garage slab

Tim,

Have you ever opened the T&P and checked to see how those actually work in: a) not spraying water all over, b) keeping up with the flow of water from the T&P?

Keep in mind that you are only testing it at "house pressure" (not to exceed 80 psi) and not at 150 psi where it will blow off.

[Tim Saunders]

Tim,

Have you ever opened the T&P and checked to see how those actually work in: a) not spraying water all over, b) keeping up with the flow of water from the T&P?

Keep in mind that you are only testing it at "house pressure" (not to exceed 80 psi) and not at 150 psi where it will blow off.

Yes test whenever practical, I would just as soon find out during my inspection if the drain system is correct, instead of finding out later.
In this one there is a little over spray at house pressure, I have never seen a T&P open as intended, I have seen them drip

[Richard Stanley]

If the TP terminated just above the floor, that would seem to comply with #2 & #5. I think it could terminate just above the pan also as the pan is a waste receptor. Code does not prohibit this.

[Ron Hasil]

If the TP terminated just above the floor, that would seem to comply with #2 & #5. I think it could terminate just above the pan also as the pan is a waste receptor. Code does not prohibit this.

Here in Illinois the code says you can not discharge the P&T vavle into the safe pan.

"The relief valve discharge pipe from the water heater is not allowed to discharge into the pan drain piping and must be piped independently to an approved air gap indirect connection to a receptor or floor drain located in the same room as the water heater. ”

[Jerry Peck]

If the TP terminated just above the floor, that would seem to comply with #2 & #5. I think it could terminate just above the pan also as the pan is a waste receptor. Code does not prohibit this.

The code does not prohibit that, you are correct.

However, think of the implications of doing that (and that method is used all to frequently).

You drain the T&P to the pan under the water heater. The water heater is setting directly DOWN IN the pan. The pan drain is installed through the side of the pan and leaves about 1/2" of water in the pan which cannot drain out. The water heater is now setting in that 1/2" of water. The water heater is not allowed to be partially submerged, and it is - call or e-mail any manufacturer and ask them if their water heater is allowed to be partially submerged in water, every one will say no, water heaters are not allowed to be partially submerged in water. I have also not found any water heaters listed for being submerged or partially submerged in water.

Some areas, like Ron stated above, do not allowed that. *I* believe *NO AREA* should allow that - it just does not make any sense to allow the T&P to discharge to the pan under the water heater.

[Richard Stanley]

This takes me back to previous threads -- How often, if ever, is that TP going to trip? Mostly -- never. As far as water in the pan goes - that is what the pan is for - a leaking wh. - that, I suspect, is also rare. Remedy is replacement. Is it better to install one of them there ....urinals (see pic in post #8.?

[brian schmitt]

This is acceptable for water heaters in conditioned areas
The pan drain is connected to the sewer, the T&P extension drains the belled PVC which discharges onto the garage slab

Hope this helps

Tim
tim,
i'm not too keen on the pan being connected directly to the sewer as sewer gas can enter the area unless a trap was used?

[Jerry Peck]

This is acceptable for water heaters in conditioned areas
The pan drain is connected to the sewer, the T&P extension drains the belled PVC which discharges onto the garage slab

Hope this helps

Tim


tim,
i'm not too keen on the pan being connected directly to the sewer as sewer gas can enter the area unless a trap was used?

Tim would need to verify, but I am presuming that the pan would connect to the sewer via an air gap and indirect waster receptor (which would be trapped), which would eliminate that concern.

[Ron Hasil]

This takes me back to previous threads -- How often, if ever, is that TP going to trip? Mostly -- never. As far as water in the pan goes - that is what the pan is for - a leaking wh. - that, I suspect, is also rare. Remedy is replacement. Is it better to install one of them there ....urinals (see pic in post #8.?

More often than you think. I get calls on them tripping all the time. Most of them are where an RPZ or some sort of backflow preventer was installed and someone failed to install an expansion tank. So when thermal expansion happens it causes the P&T valve to trip.

[Jerry McCarthy]

Water heaters are programmed to fail exactly 3 days after the termination of their warranty. It's called job security for the water heater industry. Anyone who thinks a WH drain pan doesn’t fill with water during failure of the WH should not be inspecting homes. The code folks know this fact and thus have a code application for a drain-pan drain line. Also, the WH PTRV should not terminate into the drain-pan as the code folks also recognize that fact that the quick volume release from the PTRV would overcome the drain-pan capacity and thus its drain line and overflow causing water damage including potential scalding. There appears no way nice to say this, but if you cannot comprehend this simple technology Sears is looking for some salespersons for their vacuum cleaner line.

[Tim Saunders]

Tim would need to verify, but I am presuming that the pan would connect to the sewer via an air gap and indirect waster receptor (which would be trapped), which would eliminate that concern.

Jerry, the pan drain connects to the tub drain above the tub trap.

Have a great day
Tim

[Richard Stanley]

"causing water damage including potential scalding"
Apparently those 'code folks' had brain lock when they prescribed #5 draining to the floor and #6 not causing damage. Perhaps they could fill the openings at Sears / Kmart.

[Jerry Peck]

Jerry, the pan drain connects to the tub drain above the tub trap.

Tim,

Directly connected, or indirectly connected through an air gap?

Directly connected is not allowed.

[Matt Vozzella]

"causing water damage including potential scalding"
Apparently those 'code folks' had brain lock when they prescribed #5 draining to the floor and #6 not causing damage. Perhaps they could fill the openings at Sears / Kmart.

That's why I try to take the T&P outside in my design. Local permit office and inspectors allow this as long as it is in a noticable place (i.e. landscaping). I had a discussion with my boss (engineer) about this thread yesterday. He doesn't like to terminate the T&P inside the room if at all possible due to potential injury.

Some areas allow plastic pans, a T&P blowing will destroy a plastic pan.

[Jerry Peck]

That's why I try to take the T&P outside in my design.

Does not matter if you like it or do not like it terminating inside, it is REQUIRED TO.


Local permit office and inspectors allow this as long as it is in a noticable place (i.e. landscaping).

They should be reported to the state for not enforcing the code AS THEY ARE REQUIRED TO DO.

All you need to do is terminate it inside, through an air gap, into a large enough opening, with enough volume, and sufficiently sized drain from it WHICH GOES TO THE OUTSIDE and you have accomplished the goals of the code and what you and your boss want (and what I would like to see as an inspector).

Florida Plumbing Designer's plans would never pass inspection with a proper code inspection. The local building department does not have the authority to make those changes.

I know, that is the way the T&P USED TO BE ALLOWED to drain - to the outdoors, I liked it better than to the indoors, but we must all stay within the code's current requirements or we are doing ourselves and our clients a disservice.

[Matt Vozzella]

What can I say except that it is allowed - Lee, Charlotte and Collier counties have all allowed it. If you wish to report them I've listed the counties above, also the cities of Bonita and Cape Coral as they have their own review departments.

I happen to agree with my boss, obviously, and have never had the issue questioned in those jurisdictions. I may have done it in Palm Beach, Deerfield Beach and Fort Walton Beach as well but those plans were a few years ago.

My bosses OE insurance premiums and limits is quite high given an ME's liabilities. He does not tend to be flippant about personal safety issues. In the 10+ years I have known him the only lawsuit that has ever come up regarded a noisy kitchen exhaust wallcap. We have and do currently work for major municipalities (counties and cities), schools and medical corporations. We have kept them as clients due to excellent design with little or no issues with their buildings as far as work is concerned.

I know you are going to say things must be installed as the code is written but on our end safety and practicality must be taken into account. For inspectors it would be perfectly expected to comment on the layout, for us it's another story.

[Richard Stanley]

Things must be installed, built, etc. per code IF that code is in effect, adopted with or without exceptions by the appropriate jurisdiction.
Personally, I would rather see the tp terminate to the exterior.

P2801.5 Required pan. Where water heaters or hot water storage
tanks are installed in locations where leakage of the tanks
or connections will cause damage, the tank or water heater
shall be installed in a galvanized steel pan having a minimum
thickness of 24 gage (0.016 inch) (0.4 mm) or other pans for
such use. Listed pans shall comply with CSA LC3.

From the commentary

Where leaks from a water heater or storage tank or the
associated connections will cause damage to the
structure, the tank must be installed in a drain pan. The
pan must be constructed of galvanized steel or other
material intended for such use. Where listed pans are
used they must conform to the requirements of CSA
LC3. Such a pan is intended to catch water from a
leaking tank, a leaking connection to the tank or condensate
from the tank. The relief valve discharge piping
is prohibited from terminating into such pan (see
Commentary Figure P2801.5). A 3/4-inch-diameter
(19.1 mm) pan drain is not capable of carrying the
pressurized discharge of the relief valve at full flow.
See Section P2803.6.1.

[Jerry Peck]

Things must be installed, built, etc. per code IF that code is in effect, adopted with or without exceptions by the appropriate jurisdiction.
Personally, I would rather see the tp terminate to the exterior.

P2801.5 Required pan. Where water heaters or hot water storage
tanks are installed in locations where leakage of the tanks
or connections will cause damage, the tank or water heater
shall be installed in a galvanized steel pan having a minimum
thickness of 24 gage (0.016 inch) (0.4 mm) or other pans for
such use. Listed pans shall comply with CSA LC3.

From the commentary

Where leaks from a water heater or storage tank or the
associated connections will cause damage to the
structure, the tank must be installed in a drain pan. The
pan must be constructed of galvanized steel or other
material intended for such use. Where listed pans are
used they must conform to the requirements of CSA
LC3. Such a pan is intended to catch water from a
leaking tank, a leaking connection to the tank or condensate
from the tank. The relief valve discharge piping
is prohibited from terminating into such pan (see
Commentary Figure P2801.5). A 3/4-inch-diameter
(19.1 mm) pan drain is not capable of carrying the
pressurized discharge of the relief valve at full flow.
See Section P2803.6.1.

However, THE REASON that the water heater drain pan drain line MATERIAL was changed in the 2006 code cycle was because it is allowed by code to drain the T&P to that drain pan, and the PVC drain line which had been allowed in previous code cycles was not rated for hot water, the new material reference no longer allows PVC for that drain line - for that very reason.

IT WOULD BE NICE is the code did not allow the T&P to drain to the drain pan, but until the code says same, it is allowed. Unfortunately - I would like it to not be allowed as then the water heater would only set in water when there was a leak in the water heater or the piping at the water heater.

[Jerry Peck]

Matt,

Not to worry, I'm not going to turn them in. If I was inspecting over there I might.

The point is that the inspectors themselves are required to enforce the code, not their personal wishes and the building departments are required to enforce the code, not their personal wishes, and if they wish differently than the code than there is a process where they submit their local amendment to the state where it is reviewed and either allowed or disallowed, and if allowed it may well be in the code the next code cycle.


What can I say except that it is allowed - Lee, Charlotte and Collier counties have all allowed it. If you wish to report them I've listed the counties above, also the cities of Bonita and Cape Coral as they have their own review departments.

I agree that it should be allowed to drain outside, but it is not, *it used to be* allowed, but *is not* allowed any more.

[Matt Vozzella]

Jerry,
I wouldn't be too concerned if they decided to enforce the rule. That would mean I'd have to draw one less line and note differently ;) . It isn't too unusual to get comments on plans, it lets the reviewer feel like they are doing their job, and sometimes they do just to show their ignorance.

I just wanted to throw a different point of view out there, one which I think is valid. This site has a lot of good information in it for my own personal education and it mkes me feel good to contribute ;) and hopefully I don't show ignorance on my part...often.

[Tim Saunders]

Tim,

Directly connected, or indirectly connected through an air gap?

Directly connected is not allowed.
Jerry, it is directly, there is a close in and a final plumbing inspection from the local jurisdiction.

Have a great day
Tim

[Richard Stanley]

I found it strange that the code does not prohibit the tp terminatation in to the pan, but, the commentary does.

[Jerry Peck]

I found it strange that the code does not prohibit the tp terminatation in to the pan, but, the commentary does.


That is probably the first step is trying to convince enough people to put it into the code. :)

[Jerry Peck]

I just wanted to throw a different point of view out there, one which I think is valid.

Matt,

It is a valid point, but you need to understand where the code was before.

The code did allow the T&P discharge line to discharge to the exterior, and it stated that the line should not be trapped, drain dry by gravity and all.

However, many ... MANY ... plumbing code officials and inspectors deemed that the T&P discharge line was only that portion which was connected to the T&P and went to a "riser", which no longer needed to meet those requirements.

What that resulted in was water heater being installed with the T&P "discharge line" going horizontal and slope downhill, entering an elbow to "a riser", i.e., it drained downhill from the T&P valve opening to "the riser", then "the riser" went down into the ground, across under the slab, then back up (creating a trap "in the riser" but not in the T&P "discharge line"), another elbow, a horizontal piece of pipe, another elbow, and the discharge was outside facing down.

Completely and totally wrong all the way.

How to stop that practice? Require the T&P discharge to terminate in an air gap "in the space the water is located in". There no longer was a "riser", it stopped right there, at the space the water heater was in.

And that, as Paul Harvey would say, is the rest of the story. :)

[Michael Chambers]

Based on the conversation in this thread therefore, then I suppose you all would not approve of this particular installation. :D

I do have a serious question on the TPR drain tubing being used. I don't have access to the code involved, but common sense and intuition tell me that the drain tubing cannot be flexible. Is this correct?

Thanks a lot!
_________________
Mike Chambers
BrickKicker Home Inspections

[Rick Cantrell]

"common sense and intuition tell me that the drain tubing cannot be flexible. Is this correct?"


Yes, you are correct.