Do I need this pipe

[DarrenS]

Hi All
Hoping to get an experts opinion here.
I just purchased a house with a pool and am doing my own maintenance.

My water is looking good, but one of my pipex has sprung a small leak at the joint. Simple enough to fix, but my issue is I don't know why the pipe exists in the first place.
The pipe is a flexible hose the tees off from the pump, goes through a valve and directly to the returns, bypassing the filters and chlorinator.
I've linked to some pictures of this, as it'll probably make more sense.

https://www.flickr.com/photos/125327010@N08/

My question is simple. Do i need this pipe and if so, what in the heck is it doing.

Thanks Pool gurus.

 

[Nuvene]

It sounds like it was just added in after everything was set up to add the ability to recirculate the water without running it through the filter. It probably isn't needed, but it is a nice feature to have if ou ever have the need to bypass the filter.

 

[DogsHouse_MyPool]

I know you said its leaking, but can you clarify, is the valve for it open or closed? It appears it is only about 3/4 in while the rest of your plumbing looks to be 2 in. I also don't see a valve on the main line that would allow this line to carry a bypass flow. As a result, I think it might be more of a pressure relief setup. My guess is its to allow the filter to run clogged by eliminating excessive back pressure. That sounds a lot easier, to install a bypass, than to clean the filter when it starts to clog.

- - - Updated - - -

Picture this, the old pool guy didn't want to have to come out more than once a month to clean the filter, and one month it clogged before he could get there, causing another plumbing problem he had to fix on his dime. This pressure relief might prevent that so his monthly cleaning schedule could work, at the expense of clean water. Again, just a guess....

 

[timerguy]

Looks like a boost pump line for a cleaner maybe. At least that's what mine looks like.

https://www.dropbox.com/s/jexe7zlslo9shbg/2014-07-11%2010.31.36.jpg

 

[DarrenS]

Thanks for the replies.

I think Doghouse may have hit the nail on the head. When I took over the pool, the pool company maintaining it for the previous owners had done a great job turning the pool green. As I was travelling for work, my wife hired them to get it straightened out. After 2 weeks they still hadn't figured it out.
I managed to turn it clear in 48hrs and also discovered the filter system was running at close to 40psi. I tore it apart, cleaned it good and am now running at 14psi. So a pressure bypass makes sense.
I closed the valve to see what happened, it raised the tank pressure about 1psi and the pump sounded a little more labored but not stressed. Other than that everything is running and the water is clear and moving right.

I couldn't figure a reason for it, and wanted to check before i remove it.

Timerguy - I thought the same, but I have 2 other lines that make sense for the boost pump. The line in question overlaps the other 2, so a little tricky in the pics to separate them.

Thanks again guys - This forums been great.

 

[timerguy]

Confusing pics to be sure. You have two different pipes labeled as mystery. Way too many arrows especially on the boost pump pipes. Glad you got it figured out!