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· JOATMON
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Discussion Starter · #1 ·
My inspector me be easy to get along with...but he is not one to cut me any slack on things being done right.

I'm ready for my plumbing inspection (2-story addition)....and he want's me to fill all of my drains with water for a leak test. This means I have to cap (again) the main 3" line where it connects to my existing sewer line underneath the house....

In this pic, that point is just before the pipe goes into the footing...



I have all the rubber caps...(I thought about gluing on ABS caps but the rubber ones are just as cheap...and I can reuse them)

Doing some quick calculations...it's about 25' from the crawl space to the top of my lowest vent stack...that works out to about 10.8 psi of water head at the bottom of the plumbing run.

Can those rubber caps handle that kind of pressure?

I already have the washer/dryer installed and working....so I need to plug the hole in the washer drain....for that I was going to use one of these.....it could have as much as 8 psi on it. Can it take it?



On the ground floor, I'm thinking that maybe I should use the ABS caps glued to the pipes...then cut them when I'm ready to actually install the drains.

Input?
 

· Premium Member
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The cap will hold on the building drain, I wouldn't trust the expansion plug down there.
It should do fine on the washer box though- I'd put a thrust block on top of it- braced against something- I have seen a lot f them blow out of floor drains.
Can I watch you go in the crawler and pull the cap after you're signed off?:jester: I know its more money put think about a 4" test balloon in the ext. clean out
 

· JOATMON
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Discussion Starter · #4 ·
The cap will hold on the building drain, I wouldn't trust the expansion plug down there.
It should do fine on the washer box though- I'd put a thrust block on top of it- braced against something- I have seen a lot f them blow out of floor drains.
Can I watch you go in the crawler and pull the cap after you're signed off?:jester: I know its more money put think about a 4" test balloon in the ext. clean out
Yea.....I'm sure you would 'love' to see that......

Actually....it's going to be easy....I have a cleanout at the other end of that main line you see....just outside the back wall....I'll just remove the cap and watch the water shoot out out 15'. Then I'll take my shop vac and shove the hose down the pipe and suck up about 90% of the water....takes all of about 3 min....then when I climb under the house I only get about a 1/2 gal of water on the ground....our clay soil sucks it up pretty quick.
 

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ddawg- horizontal plastic drain lines need support @ 4ft spacing and every change of direction- might want to add a hanger at the left side of the picture- unless you're setting up the inspector so he can write a correction- that way he feels like he's done his job :thumbsup:
 

· JOATMON
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17,849 Posts
Discussion Starter · #7 ·
You don't actually pressurize the DWV. You just fill it water. The only pressure comes from the head of water which is about .4 PSI per foot of rise.
25' of head? (10.8 PSI).....yea...my bottom section of DWV will be under pressure....no matter what you call it....but that is a pressure test....

ddawg- horizontal plastic drain lines need support @ 4ft spacing and every change of direction- might want to add a hanger at the left side of the picture- unless you're setting up the inspector so he can write a correction- that way he feels like he's done his job :thumbsup:
Funny you should bring that up....I was just looking at that....I found a table that showed the pressure limit for ABS (3" is 100PSI +)...it also showed the max distance for support of each size of pipe....

So, yes, I will be adding a strap or two down there tonight. On a bright note (pun intended), I now have lights so I don't need to take a light with me...

And BTW....great idea about the wood block on the washing machine....I could see that one going airborn...

I'm just going to go ahead and glue caps on the bottom sections....
 

· JOATMON
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17,849 Posts
Discussion Starter · #8 ·
Well.....I got everything plugged up and all the pipes strapped....and I followed eplumbers advice....I put a block above the plug in the washer box.



Lines are full of water....water level is maybe a foot or two from the roof.....I'll top it off tomorrow when the inspector shows up....but at least there is no leaks...
 

· Registered
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You don't actually pressurize the DWV. You just fill it water. The only pressure comes from the head of water which is about .4 PSI per foot of rise.
Well, had I been required to test my DWV piping, it would've been filled to the top of the soil stack. That would've been a 27-ft water column, or more that 12 psig pressure on piping and fittings not designed for pressure.
 

· Doing it myself
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We're only required to fill up to the lowest fixture on the highest floor. IE : If there's a tub, we fill to the overflow on the tub. If there's a shower, we fill the shower pan to the rim. If there's just a split drain waiting for the tile guy to do the membrane, we fill that shower drain to the top. If we have a washing machine box and no tub, we fill the washing machine box.

Normally on single story tests we just use glue in test caps. The hold pretty well even on two story most of the time if the person installing it did a good glue job. :whistling2:

I wouldn't trust those expansion plugs though. Just did a rough in test the other day at 5 psi, and when we came back monday to pull the equipment off one of them was leaking.

Speaking of which, glad we got that rough in done, because it's raining today.

:thumbup:

I prefer the neoprene caps with the hose clamp on them. If you need an internal plug i'd use a balloon.
 

· JOATMON
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17,849 Posts
Discussion Starter · #11 ·
I used the rubber caps on all the open lines (Sinks, toilets, etc). They seem to be holding quite nicely...

But....my clean out cap is leaking....I put Teflon tape on it....but I guess that is not enough....it's a real slow leak....more like a drip.....I'm hoping he does not sweat me on that one since it's outside....and if water is coming out that during normal operation....I have bigger issues.
 

· JOATMON
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Discussion Starter · #12 ·
One last question....

If you go to the top of this thread and look at the 1st photo....where my sewer line goes through that foundation wall...just before that is where I capped the line. Got out the old sawzall and cut it...I have about a 1" section cut out....I have one of those rubber sleeves to seal it back up....but I'm not real excited about having that 1" gap....

My concern is that 'stuff' could get caught on the lip going into the pipe....am I being worried about the wrong things?

How do you guys do it?

One thought is to cut out a larger section...cut a splice that fits snug between the two pipes and use two rubber sleeves.
 
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