The dang backwash pipe split

[JJ_Tex]

So... yesterday after cutting the grass for the first time and kicking up a ton of dormant bermuda grass dust into the pool, I decided to backwash once the skimmer did its job and sucked up all of said dust. After dinner I went out and kicked the pool into service mode, turned the multi-valve to backwash, then fired up the pump to begin the process just like I have done many times in the past.

This time when I turned on the pump the pipe that takes the backwash water underground and to the sewer split. From what I could tell it cracked at the elbow in the pipe and then the long pipe split lengthwise right before my eyes.

It should be a pretty straightforward fix of the PVC, but I'm really confused as to why this occurred. Do you think it could be some sort of blockage in the line that caused the split? Should I try and snake the line before the repair? Maybe there was water in the line and a freeze got it? Anyone have any ideas on why and what I need to do other than fix the PVC?

 

[Newdude]

Maybe there was water in the line and a freeze got it?

Either this time or last time like the SWG union. But now its 2 the forst time they fored up so i'll guess this year. The pump doesn't have the PSI to split pvc.

In pic 2 the pipe coming out of the ground isn't plum (perfectly vertrical) like the other pipes. so the pipe that cracked is the low spot that won't drain fully by itself. The good news is you can give it some pitch while replacing it and it will never bother you again.

 

[JJ_Tex]

The pump doesn't have the PSI to split pvc.

Ok good. So even if I had the pump on full blast and there was some sort of complete blockage in the pipe it would not split? I was worried I might have some sort of bigger problem underground.

 

[kimkats]

I think Dude is right BUT..............I would make sure the end where the water comes out is open and not blocked. I can see some dirt or such blocking the flow and causing this problem. I would also snake the line to be on the safe side.

 

[Newdude]

Ok good. So even if I had the pump on full blast and there was some sort of complete blockage in the pipe it would not split? I was worried I might have some sort of bigger problem underground.

You would 'dead head' the pump and it would be the weak link that snapped.

It cannot hurt to explore the pipe and you won't have that chance again.

 

[kimkats]

Time for Dude to teach the teacher!

Talk to me about this please:

'dead head' the pump

 

[Newdude]

Talk to me about this please

The pump doesn't have enough PSI to break the pipes in a blockage situation. So the flow stops, but without new cold water the water inside the pump quickly overheats to the point of failure.

Then you still have a blockage and a dead pump.

 

[ajw22]

The pump doesn't have enough PSI to break the pipes in a blockage situation.

Sometimes a weak glue joint will pop a leak with the pressure of a dead headed pump. But the pressure is not enough to bust schedule 40 PVC pipe.

I agree the crack is most likely from freezing. Other cause could be too may people steping on that pipe. Looks to me like its placement is likely to be stepped on.

 

[Newdude]

Sometimes a weak glue joint will pop a leak with the pressure of a dead headed pump

Especially on a waste line if using DWV fittings.

Time for Dude to teach the teacher!

Talk to me about this please: dead head the pump

*not to be confused with Jerry Garcia fans with multi colored teddy bears.

 

[Dirk]

I won't pontificate on what was the last straw for that pipe. Nor on I why I felt the need to use the word pontificate. PVC pipe gets brittle after prolonged exposure to UV, so that was very likely a factor on why it gave out. The heat radiating off the concrete didn't help either. Once you complete the repair, give all your PVC a good coat or two of latex paint, which is recommended by PVC manufactures for above-ground PVC. They also warn not to use oil-based paint. Lighter colors are best, as dark colors transfer more heat to the PVC.

You might also consider getting it off the concrete. If you moved it forward, over the white rock, that would give it some air, and also give you more room to walk. If you were looking for something else to do, you could do the forward jog next to the valve, and run the whole pipe underground in a shallow trench just in front of the slab. That's what I did with my solar pipes, just so they'd be protected and so I wouldn't have to look at 'em...

 

[Newdude]

If you were looking for something else to do, you could do the forward jog next to the valve, and run the whole pipe underground in a shallow trench just in front of the slab.

+1

(With the appropriate pitch)

 

[JJ_Tex]

As a quick update, I cut the pipe out (well most of it) and was able to snake the line. There was standing water in it and I got some DE residue to come out. Then I hooked up a shop vac into the cut end by the pad, then by the sewer cleanout and was able to get suction on the other end of the pipe, so I'm confident I do not have any sort of blockage anymore.

I went out and got the PVC for the fix, got everything dry fit into place and did a brief test run of the backwash valve. Water was going into the sewer trap, but I also noticed there is a crack I missed in the 90 degree elbow right before it goes underground.

I do not have a lot of room in this spot. Would flexible PVC (schedule 40) be an option for me?

 

[Newdude]

Can you dig up a little and splice it below grade ? Or is there concrete or something else that stops you from exposing more pipe?

Rigid PVC is always better but there are many flex PVC pools out there. Plus if it ever broke, you now know how to fix it. So there is that.

 

[JJ_Tex]

Ok, I now have my new and improved backwash line complete with a shutoff valve (doubt I will need but figured it may come in handy if I had a multi-port leak or when trying to clear the line), as well as a screw off cleanout if I ever needed to snake it again without cutting the pipe. And just for @Newdude I angled it downwards and was able to work with the pipe that was above ground so no digging required. Thanks everyone for your help.

 

[Dirk]

Looks good. Now paint it so it won't happen again! If ya don't mind me sayin'...

PS. Nice glue joints, I can never make mine disappear like that.

 

[Newdude]

And just for @Newdude I angled it downwards

Phew. Thanks man. Replacing this was such a pain for me. Good lookin out

Does the first half have some pitch? I mean. You know how to fix it now, but I'd rather you never have to again.

 

[JJ_Tex]

Does the first half have some pitch? I mean. You know how to fix it now, but I'd rather you never have to again.

A little, but I didnt want to cut too close to the multi port valve, so that piece is the original slope. The new stuff I put in by the ball valve has a slight slope until it hits the 45 degree coupling going downward. I plan to blow out that line before next winter to hopefully keep this from happening again. Its also elevated off the concrete just in case someone stepped on it to cause the issue.

 

[Newdude]

A little,

It doesn't take much the old one was uphill at the 90 to the ground. That's no Bueno.

 

[JJ_Tex]

PS. Nice glue joints, I can never make mine disappear like that.

Thanks. I also have some decorative purple rocks now. I guess it is fitting with Easter coming up soon.