Backwash line

colonelkirby

Silver Supporter
Mar 20, 2017
166
DFW - Plano, TX
Pool Size
25500
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Had some work done that included a new backwash line. Noticed that it was travelling uphill from the bottom of the slide valve to where it 90s to the outlet to the sewer. Should I be concerned? Freezing temperatures seems to be a potential issue.

TIA

20221231_111252.jpg
 
It's hard to tell from the pic, but it looks like only a little water will be trapped. Ice only expands about 10% so it only needs that much room and your pipe can be 90% full without harm. Put a level on the bottom of the horizontal pipe on the left side to see how much water will be trapped there.

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If you paid for the work to be done, you could easily argue shoddy work in requesting a redo.
 
What is the brass thing?

It's hard to tell where level is.

Can you show the actual level?

I would want it to be level.

How long is the waste line?

I would also want a vacuum breaker so that the line can drain.

You can remove the cleanout plug and install the vacuum relief there.




I would estimate level at the red line, but it is difficult to tell for sure.

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The AAVs are not really designed for the application, but they should work well enough for the purpose.

There should not be enough back pressure to cause the AAV to leak or fail.

You might have codes related to waste lines and you should comply with any local codes.

You can also use a solar vacuum breaker.



https://shop.solardirect.com/product_info.php?products_id=304
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If we use the level, it appears that the slope is about 1.5" upward from the filter to the 90 going down.

If the filter is level (Vertical slide valve) and you use a 90, then you would expect the pipe to be level (Horizontal).

Is the slide valve perfectly level?

Without a vacuum breaker, the water won't drain and you can get water hammer if the waste line is long and if the line slopes down by a lot.

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It's hard to tell where level is.
Upon another look, I now see the level sitting there. 🤦‍♂️ That's were the level is. :ROFLMAO:

On a serious note, if we can assume the pad is level(ish), then the pipe is off more than we assumed at first.
 
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Thanks for the thoughts y'all. I recall the brass fitting as being described as a vacuum break to aid in draining. (looks like a fitting I had on a sprinkler line at one time) Prior to this work being done, there was nothing like that present, no sight glass nor clean out. The slide valve is reasonably perpendicular to the pad and the filter is level. I'm having the folks back out to address. Level or even slightly downhill is the goal right?

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The problem is that the line is not flexible and you can't just force it down.

If the horizontal line is off, then it seems like the filter and slide valve have to be off by the same amount if the fitting is a 90 degree fitting.
 
If the horizontal line is off, then it seems like the filter and slide valve have to be off by the same amount if the fitting is a 90 degree fitting.
Or the vertical pipe on the left is too tall and it's jacking the rest of it.
 
The pad seems like it has to be off level?

The pump suction seems to be roughly parallel to the waste line, which would mean that the pump and pad are sloping backwards.

Did you measure the pad in all directions to see is it is perfectly level?

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Or the vertical pipe on the left is too tall and it's jacking the rest of it.
The pipe is not flexible, so you really can't just push up on the pipe that much.

It would force the slide valve and filter to lean back.

It might be possible to force it to be off that much, but it would create a lot of stress in the pipes.
 
The bubble in the level looks like it is centered pretty well, so maybe the pad is level?

Once you cut the waste line, you will be able to tell if it is under a lot of stress.

It seems to me that getting it level might not be easy.

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To me, it looks like the pad slopes backwards, but it is hard to tell for sure.
The original level looks level but you hafta squint to see the bubble.



Screenshot_20221231-170132_Gallery.jpg


It's one thing if camera angle was playing mind tricks on us, but these 2 pipes should be parallel if so. And they go away from each other instead.

Screenshot_20221231-170318_Chrome.jpg
 

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