# TPR goes outside but drip pan onto floor? **URL:** \ **Category:** Plumbing Inspections\ **Created:** [August 29, 2014, 9:46am UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437 "2014-08-29T09:46:44Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![mkoester](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/mkoester/32/1446_2.png) [@mkoester](https://forum.nachi.org/u/mkoester)\ **Post date:** [August 29, 2014, 9:46am UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/1 "2014-08-29T09:46:44Z")
I am wondering if they plumbed these backwards. Drip pan overflow pipe drains onto floor below while TPR is plumbed to go outside through (3) 90 degree angles. ![20140828_104608.jpg](https://global.discourse-cdn.com/internachi/original/3X/a/1/a1c07d0b2bcbcdcf1419d9199224b52eb4d688c3.jpeg) ![20140828_104618.jpg](https://global.discourse-cdn.com/internachi/original/3X/4/a/4a7de8c0c1e5c9860d6203daaabe7512ae653b50.jpeg) ---
**Author:** ![canderson5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/canderson5/32/1814_2.png) [@canderson5](https://forum.nachi.org/u/canderson5)\ **Post date:** [August 29, 2014, 10:21am UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/2 "2014-08-29T10:21:02Z")
That pretty much turns the drip pan into a big coaster. 🙂 What’s the problem with the 90° fittings? Going outside is wrong, but I don’t see an issue with the 90° fittings in and of themselves. > [@](#): > > 2012 IRC > 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 the pan serving the water heater or storage tank, to a waste receptor **or to the outdoors.** > 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 P2905.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1. Hmm, not sure those two make sense… ---
**Author:** ![ddagostino](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/ddagostino/32/60136_2.png) [@ddagostino](https://forum.nachi.org/u/ddagostino)\ **Post date:** [August 29, 2014, 12:02pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/3 "2014-08-29T12:02:11Z")
The older CPVC pipe indicates that at the time of original installation, the TPR discharge was routed to the exterior (common at the time). The overflow pan was routed to the floor below as to not damage the platform. Dom. ---
**Author:** ![rlewis5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/rlewis5/32/337040_2.png) [@rlewis5](https://forum.nachi.org/u/rlewis5)\ **Post date:** [August 29, 2014, 12:08pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/4 "2014-08-29T12:08:00Z")
From what I see they drain the WH throught the pan drain which make the pan useless. Water can’t get out. Everything else is good. ---
**Author:** ![canderson5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/canderson5/32/1814_2.png) [@canderson5](https://forum.nachi.org/u/canderson5)\ **Post date:** [August 29, 2014, 12:33pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/5 "2014-08-29T12:33:24Z")
> [@rlewis5](#): > > From what I see they drain the WH throught the pan drain which make the pan useless. > Water can’t get out. **Everything else is good**. How about #2 above? ---
**Author:** ![badair](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/badair/32/166699_2.png) [@badair](https://forum.nachi.org/u/badair)\ **Post date:** [August 29, 2014, 12:44pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/6 "2014-08-29T12:44:50Z")
That pretty much turns the drip pan into a big coaster. What’s the problem with the 90° fittings? Going outside is wrong, but I don’t see an issue with the 90° fittings in and of themselves. Quote: 2012 IRC 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 the pan serving the water heater or storage tank, to a waste receptor or to the outdoors. 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 P2905.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1. Hmm, not sure those two make sense… Quote: Originally Posted by rlewis5 View Post From what I see they drain the WH throught the pan drain which make the pan useless. Water can’t get out. Everything else is good. How about #2 above? Cam [http://www.nachi.org/forum/attachments/f22/51840-whats-wrong-wh-water-heater.jpg](http://www.nachi.org/forum/attachments/f22/51840-whats-wrong-wh-water-heater.jpg) ---
**Author:** ![rlewis5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/rlewis5/32/337040_2.png) [@rlewis5](https://forum.nachi.org/u/rlewis5)\ **Post date:** [August 29, 2014, 1:07pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/7 "2014-08-29T13:07:00Z")
I was not referring to the PRV drain . I was referring to the pan. Since the pan drain now has the WH drain line it it. If the WH started to leak where would it drain to the exterior. I see what you are referring to, but that I haven’t see . ---
**Author:** ![rlewis5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/rlewis5/32/337040_2.png) [@rlewis5](https://forum.nachi.org/u/rlewis5)\ **Post date:** [August 29, 2014, 1:09pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/8 "2014-08-29T13:09:48Z")
Is there anything incorrect with this statement? According to present day requirements, water heaters should have a pressure relief valve and drain line which flows by gravity to the exterior, or downward to within 6 inches of the structure floor. The size of the drain line should match the outlet size of the relief valve, and an auxiliary pan with a 1" drain line which drains to the exterior is required underneath when the unit is installed at or above the level of the living area. ---
**Author:** ![mkoester](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/mkoester/32/1446_2.png) [@mkoester](https://forum.nachi.org/u/mkoester)\ **Post date:** [August 29, 2014, 1:22pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/9 "2014-08-29T13:22:00Z")
The TPR drain line runs down and then horizontally along the wall for 10 feet before 90ing through the wall to outside. It is hard to see but there is a gap between WH drain and overflow line, however that empties directly onto the concrete floor below (which showed evidence of pooling). So, would I write this as “recommend routing water heater pan overflow line outdoors” & TPR Valve as “functional” ? ---
**Author:** ![canderson5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/canderson5/32/1814_2.png) [@canderson5](https://forum.nachi.org/u/canderson5)\ **Post date:** [August 29, 2014, 10:06pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/10 "2014-08-29T22:06:04Z")
I don’t think the TPRV can be considered functional until it discharges through an airgap inside the same room as the water heater. ---
**Author:** ![rlewis5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/rlewis5/32/337040_2.png) [@rlewis5](https://forum.nachi.org/u/rlewis5)\ **Post date:** [August 29, 2014, 10:42pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/11 "2014-08-29T22:42:26Z")
That I have read, but why not outside of the room? ---
**Author:** ![canderson5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/canderson5/32/1814_2.png) [@canderson5](https://forum.nachi.org/u/canderson5)\ **Post date:** [August 30, 2014, 11:52am UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/12 "2014-08-30T11:52:28Z")
> [@rlewis5](#): > > That I have read, but why not outside of the room? The termination can be out of the room, but it must have an air gap inside the room. I read that as a standpipe or floor drain just below the end of the TPRV pipe. That standpipe can go anywhere after that. ---
**Author:** ![mkoester](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/mkoester/32/1446_2.png) [@mkoester](https://forum.nachi.org/u/mkoester)\ **Post date:** [August 30, 2014, 2:18pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/13 "2014-08-30T14:18:18Z")
So, they could have just discharged the TPR into the pan and plumbed the pan drain to the outside. That would supply a gap and leak protection. ---
**Author:** ![canderson5](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/canderson5/32/1814_2.png) [@canderson5](https://forum.nachi.org/u/canderson5)\ **Post date:** [August 30, 2014, 4:07pm UTC](https://forum.nachi.org/t/tpr-goes-outside-but-drip-pan-onto-floor/89437/14 "2014-08-30T16:07:41Z")
> [@mkoester](#): > > So, they could have just discharged the TPR into the pan and plumbed the pan drain to the outside. That would supply a gap and leak protection. Yes, though in a discharge situation it’s going to spray everywhere anyway. It’s the ability to monitor the end of the pipe for leakage which is most important in my book.