T&P valve installation?

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Can someone point me to the actual code governing installation of a T&P valve on a hot water heater? Mine just crapped out on me; I came home to a lovely few inches of water on the basement floor. Appears to have done a decent job of loosening the old vinyl floor tiles anyway (silver lining) I seem to have bad luck with plumbing; I need to invest in a better dehumidifier :(
Anyway, the reason I am asking re: code is that I don't have a floor drain (obviously) and yet the water heater's T&P valve was just plumbed with a piece of 3/4" copper straight down to the floor. I'd like to plumb it over to the deep sink, however I cannot do that while following all the instructions on the package (outlet mounted straight down but only four elbows) wondering if I could upsize the pipe to 1" to allow for an extra elbow or two. Right now I have it running into the deep sink through a garden hose which I know doesn't meet code but will at least keep the floor from getting wet again while I dial in the thermostat (shut it off all the way to drain the system down while I ran to the Despot to pick up a new valve)
Right about now is where I regret following my gut; when we looked at the house the T&P valve started going flaky and the PO's called a plumber, he said just to cycle it occasionally to keep lime etc. from building up on it and it should be fine. I thought about replacing it but didn't. Hindsight, etc. (although I was a little concerned breaking it loose from the tank; had to use two pipe wrenches as one seemed two scary due to the force I was using/bending moment...)
thanks much
nate
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Nate Nagel wrote:

City water? Backflow preventer? No expansion tank? T&P valve have a history of dumping a little water regularly? If so install an expansion tank on the system and you'll eliminate that problem. There should never be any issue of "lime, etc. buildup" if the system is working properly. If there is a backflow preventer on the system and no expansion tank, every time a batch of cold water gets in the tank and is heated with the rest of the system shut off, the pressure will spike up to the point the T&P valve has to dump.
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Well, if there should never be any issue, what then accounts for so many of them failing, like when you cycle them and then they fail to close? To say there should never be an issue if it's working properly is like saying there should never be a problem with my cars engine as long as it's working properly.

Yes, but that would result in a small amount of water fairly regularly being discharged and noticed, not a sudden big dump with inchs of water on the floor that he has.
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snipped-for-privacy@optonline.net wrote:

A T&P valve is like the valve on a fire extinguisher, it should never be operated except in the emergency situation it's designed for. Once it's been operated, then you can get the crud buildup that keeps it from sealing properly. It's not something that should be tested and once it's operated, it should be serviced or replaced.

Right, but recall he mentioned the T&P was getting hinky when he was buying the place the the PO replaced it. Sounds to me like possibly the issue I mentioned, which would lead the the gradual failure of the T&P and eventual sticking open from crud buildup. If this is the case and he simply replaces the T&P, it will likely fail again in a year or two of periodic pressure discharges.
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wrote:

T&P
home
have
(silver
a
plumbed
following
but
allow
deep
at
ran
at
from
it
breaking
two
expansion
never
properly.
They're supposed to be operated once a year.
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Yes, I've seen the advice from many sources, including WH manufacturers, that the valve should be cycled once a year to make sure it will open and is not binding, etc. And I don't understand by what mechanism occasionally opening a valve is going to cause it to develop a leak. I think if it turns out it doesn't reclose completely, that means it's bad and identified the problem, but didn't cause it.
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On Oct 20, 3:14 pm, snipped-for-privacy@optonline.net wrote:

In 25 yrs of plumbing only seen two reasons for failure temp to high or pressure which is not usual most of the time people run the tank to high and as it gets older the valve weakens cuasing it to fail or open which it should code is standard as you described in the begining. the discharge has to be lower than the valve. 4 elbows max and you can but don't have to operate it once a year. How old is the tank elec or gas and what temp is it set fore this should under normal condition never release
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jim wrote:

tank is about 18 years old and it is currently set at 130 degrees - was about 120 before. I simply can't do it with only four elbows, can I upsize the pipe to 1" or larger to compensate? There is no closer drain than the deep sink, and I need to go around a corner to get there.
nate
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According to whom? I can show you plenty of authorities that recommend operating the T&P valve manually once a year, to be sure it moves freely and water comes out. I've seen it on instruction manuals for water heaters.
Once it's

I don't see by what mechanism just opening and closing it results in crud build up that wasn't already there. If you open and close it and it doesn't shut off completely, isn't it better to find out that way, then to have it open slightly on it's own, perhaps from slight over pressure, and then fail to seat? If I open and shut any valve once a year, is it destined to then fail?

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snipped-for-privacy@optonline.net wrote:

In short - yes. The T&P valves are particularly prone, but others such as old style expansion tank drains are also susceptible. Any time you open the valve you allow water to flow past it's seating surfaces and bring with it contaminants, particularly with a valve that is rarely operated where crud can build up immediately adjacent to it and easily end up on the valve seat when it's opened. That crud allows slight leakage, usually so slight that it isn't noticed, but continues to evaporate and deposit more crud around the valve seat and the problem continues to grow.
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Pete C. wrote:

yes
not that I am aware of

no
somewhat - but I think the old one was weak to begin with.

I can believe that, but it should just make a little puddle and then reclose. The old one is full of minerals, obviously it just popped off and didn't reseal correctly. I cranked the water up to 130 degrees at the deep sink faucet and enjoyed a truly hot shower this AM, (which I could never do before, at anything over 120 degrees it would pop off fairly regularly) but didn't see any water out of the new valve, so I think that was the problem all along.
I'd still like an answer to my original question, as I'd prefer to pipe the T&P drain to the sink no matter what.
nate
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Nate Nagel wrote:

I don't have any plumbing code references to confirm any requirements for the T&P discharge piping. Logically I don't see a problem with a suitably sized piping run that open ends at the sink location.
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T&P
have
(silver
plumbed
following
ran
breaking
never
properly.
the
the
I don't know why you would try and install a water heater when you don't know the required codes that pertain to a safety device. But, I'd recommend that you have someone access the situation before you proceed. I could tell you the answer, but what says you don't do something else that's not up to code? There are to many codes governing P/T valves, you should have someone qualified to pipe your system. It's for your own protection.
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[snip]
Once again kj shows his ignorance and tries to play it as a strength. He claims to know the code (without knowing the OP's locality!) while he is actually unable to help.
OBTW, why would you suggest that someone "access" the situation? Just can't get anything correct can you kj?
(now watch the monkey boi dance)
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recommend
International Code, Dickwad. Nuff said.
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don't
Why do you call yourself names?

No, it's not. You need to learn that all building code in the US is under local control. The model codes exist as guidance for state and local authority. I'm sorry you never bothered to learn this and have to have your ignorance exposed like this.
Like I've said many times:
In other words you can't backup your foolish assertation. That's ok, it's clear you are just an incompetent fool who resorts to abusive usenet posts.
I post and you dance, monkey boi. Just keep dancing. Some day, if you don't kill yourself with your drinking habit, you'll sober up and re-read some of these posts. Perhaps then you'll realize just how foolish you were. In the mean time, just keep dancing monkey boi.
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kjpro @ usenet.com wrote:

I'm not installing a water heater. I replaced the old T&P valve and want to plumb it properly, unlike whoever installed the water heater.
I guess you must be a plumber since you seem to want me to pay big bucks to have someone else do something I could easily do it myself, instead of simply giving me a pointer to the pertinent section of code?
Bet it drives you nuts when people do their own electrical work, too.
nate
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home
it
two
recommend
Nope, it takes longer to rip out the incorrect shit and run the correct materials. That means more money in my pocket.
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kjpro @ usenet.com wrote:

Which explains why you either can't or won't give a helpful answer.
nate
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Nate Nagel wrote:

Hi, I don't know where you live, where I live T&P valve drain has to go to floor drain via copper tubing. Even PEX is not allowed per code. 18 old tank is also pretty done with. Isn't it time for new one?
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