Leaking discharge pipe?

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exm

exm

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Hi,

I have a 3 year old AO Smith Effex High Efficiency 50-Gallon Gas Water Heater. Right after installation the discharge pipe started leaking. Upon calling AO Smith, they send over a plumber and he explained that my town has high water pressure, so he installed an extension tank.

However, I noticed recently the pipe started leaking again, and also some sort of verdigris on the pipe where the extension tank sits.

What do you experts thinks is going on? Is this something to be concerned about? Thanks!

23574943720_b16ff07945_z.jpg


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expansion tank typically hooks up to the cold water line 18'' from the water heater.

if the incomng pressure to the house is above 60 psi, a prv [pressure reducing valve is also installed

the T&P valve [temp % pressure] safety valve

yours is under the expansion tank needs to be a 150 lb gauge.

the funky funk your are seeing growing on the pipe is corossion due to a very small leak.

vry small/very big a leak is a leak.

do you know the PSI of the water being delivered to your house?

if not. go to the big yellow box store with the teenager "professional" in the plumbing department

and get a d86ca1b6-06d4-4f46-bd9e-0a86b371cf47_300.jpg

screw it on the outside faucet and see what the pressure is
 
Ok, I will check my pressure and get back to this forum. The help is appreciated.

Question: does the expansion tank makes sense where it's located? Also - you mentioned a leak. What are the consequences of the leak and how can this be resolved?

Thanks all, and I'll let you know the pressure in a few days.
 
Exactly what frodo explained.

The expansion tank is meant to absorb water pressure surges due to WH heating events. If the incoming water pressure is excessive (or surges), a PRV (pressure reducing valve) needs to be installed.

The expansion tank is meant to be installed on the water inlet side (cold) as the tank diaphragm may be damaged (over time) by hot water.

Just the weight of the tank and the water it holds coming off the WH T&P relief side on a copper pipe scares me.

CORRECTION-

I see that he used a nipple to support the expansion tank. Better, but still not safe IMO.

I don't think the T&P valve is provided with a correct drain either. If it pops off, scalding may be possible to anyone standing close.
 
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KULTULZ said:
Doesn't code now require an expansion tank with a new WH install? :confused:
Click to expand...

A few things explained (hopefully)...

KULTULZ said:
I don't think the T&P valve is provided with a correct drain either. If it pops off, scalding may be possible to anyone standing close.
Click to expand...

The bottom photo shows possible result(s) of non-compliant WH install (no catch pan and/or proper T&P Valve install (no drain).

How would one ascertain proper T&P Valve blow-off pressure point, with compressed air? :confused:

WH- Thermal Expansion.jpg

WH- Thermal Expansion Explained.jpg

WH- Expansion Tank Purpose.jpg

WH- T&P Valve _1.jpg

WH- Leakage WO Pan Or Proper Drain.jpg
 
@Kultulz: great illustrations, thank you.

I called AO Smith after installation since the WH didn't produce enough hot water to fill a bathtub, and they send over a plumber who installed the expansion tank which seems to have fixed the hot water issue. The plumber explained the tank was necessary because of the notorious high water pressure in my town (I'll run the tests as soon as possible).
 
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exm said:
@Kultulz: great illustrations, thank you.
Click to expand...

You are more than welcome.

To clarify: the WH was not installed by a AO Smith provided plumber. I had major work done in my house, and the contractor simply swapped out the 20 year old WH with the new model.

I called AO Smith since the WH didn't produce enough hot water to fill a bathtub, and they send over a plumber who installed the expansion tank which seems to have fixed the hot water issue. The plumber explained the tank was necessary because of the notorious high water pressure in my town

(I'll run the tests as soon as possible).
Click to expand...

...hmmpf... How would an expansion tank install produce more hot water (not you OP)? Wonder if he simply jacked up the thermostat(s) and then installed the tank due to excessive water pressure?

Anywho...

The T&P valve is now out of code (IMO) as I read the code the probe needs to be within the tank a certain amount (unless he used a valve with an extended probe.

I wonder if A.O.SMITH paid the plumber entirely. Surely he had to submit some type of work order describing the repair(s)?

Manufacturers Instructions- http://www.watts.com/pages/support/tp.asp?catId=64

Correct Installation of T&P Relief Valves

Important Instructions: Relief Valves and Automatic Gas Shut-Off Devices

Combination temperature and pressure relief valves with extension thermostats must be installed so that the temperature-sensing element is immersed in the water within the top 6" (152mm) of the water storage tank. They must be installed either in the hot outlet service line or directly in a tank tapping. Combination temperature and pressure relief valves that do not have extension elements must be mounted directly in a tank tapping located within the top 6" (152mm) of the water storage tank. Valves must be located so as to assure isolation from flue gas heat or other ambient conditions that are not indicative of stored water temperature.
Click to expand...
 
I thought I had responded to this thread last night, but now I don't see my post?

Anyway, the temperature and pressure relief valve is installed in a manner that creates a dangerous situation. It needs to contact the water in the top 1/6 of the tank, so that it will be activated if the temperature rises to an unsafe level. The the long pipe nipple leading to the expansion tank will isolate the T&P valve from the hot water in the tank.

This needs to be remedied immediately.
 
I seriously hope the guy that came and installed this wasn't a licensed plumber. I would agree that a prv needs to be installed because inlet pressure is too high and when the water expands in the tank it puts it over 150 psi.
 
phishfood said:
I thought I had responded to this thread last night, but now I don't see my post?

Anyway, the temperature and pressure relief valve is installed in a manner that creates a dangerous situation. It needs to contact the water in the top 1/6 of the tank, so that it will be activated if the temperature rises to an unsafe level. The the long pipe nipple leading to the expansion tank will isolate the T&P valve from the hot water in the tank.

This needs to be remedied immediately.
Click to expand...


good catch, phishfood,
 
Finally got a working pressure gauge... The first one was broken (thanks Amazon!).

So the water pressure seems to be 70psi in my house (measured from an outside faucet).
 
So i would say that the relief valve is faulty and needs to be replaced and then the expansion tank removed all together.
 
stevemachine said:
So i would say that the relief valve is faulty and needs to be replaced and then the expansion tank removed all together.
Click to expand...

Thanks for the reply. I'm trying to understand why the current situation is dangerous?

Do I need an extension tank on the cold water inlet?
 
exm said:
Thanks for the reply. I'm trying to understand why the current situation is dangerous?

Do I need an extension tank on the cold water inlet?
Click to expand...

The situation is dangerous as you do not have a properly functioning Temperature & Pressure relief valve as now installed. This safety valve is meant to bleed excessive pressure (150PSI) and temperature (210 degrees) from the water heater. It's malfunction could lead to a water heater explosion (GOOGLE).

The expansion tank is needed (on cold side) to absorb pressure fluctuations (as evidenced by the leaking T&P Valve) from either external or internal pressure surges. IMO, a PRV (pressure reducing valve) should also be installed to limit the supply pressure to no more than 60PSI.

What this guy has done is dangerous and needs to be corrected ASAP.
 
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