Blocked Return Line

[Davey_crocket]

Hi Guys,
We recently moved in to a new house that came with a small (20kL) in ground pool. It has 1 skimmer and 3 return nozzles. When we first moved two return nozzles were pointed up and the other had no nozzle at all, but all were flowing.

Fast forward a few weeks to today and suddenly one of the returns has no flow at all. I managed to rod out a small disc of what looks like calcium and pebblecrete but still no flow. Also shoved the garden hose up it to try and dislodge with reverse flow but no luck. The blockage is somewhere up in the nozzle pipe further than I can reach with my fingers.

How concerned should I be? We still have excellent flow to the other two returns and still getting circulation. I guess the next step is to call a plumber to try and clear the blockage?

 

[Texas Splash]

Perhaps the garden hose application wasn't string enough? Over here we have access to products that expand in the line to provide a better seal and increased water pressure when trying to blow-out a line. Something like a Drain King or this:

 

[Jimrahbe]

Dave,

I agree with Pat's idea of using a Drain King..

But, keep in mind that the return lines are after the filter, so what could get in there to clog the line???

Are you sure the line without the eyeball/nozzle is not for something else?? What size pipes are the three lines?

Thanks,

Jim R.

 

[Davey_crocket]

Hi Guys,

Thanks for the response. I have just ordered a Drain King from an online pool supply store. It/anything like it doesn't appear to be stocked at Bunnings (Australian huge hardware store chain).

I' m reasonably certain it is supposed to be a return line as it has had return flow through it previously. Also there are no water features or redirection valves on the system other than the multiport on the filter.

Jim, i am as confused as you are about where this stuff has come from, i attached a photo the bit i did manage to get out. I can only assume it was rubble that it got in during construction.

Cheers,
Dave

 

[Texas Splash]

Those are some healthy chunks. I bet if you poured a few drops of muriatic acid on one of them it would fizzle pretty good.

 

[Davey_crocket]

It did indeed, disintegrated into almost nothing in about a minute. Now if only I could get some acid to the blockage in the return line...

 

[Texas Splash]

Now if only I could get some acid to the blockage in the return line...

Ha ha. Right! Unfortunately, since that's not an option, the best you can do is a combination of ensuring your CSI level is slightly negative (-0.1 to -0.3) and perhaps continuing with any mechanical clearing (snake) possible. This of course assuming the blockage you suspect is more of the same (calcium chunks). At some point, you may consider having someone run a scope through that line to confirm. Let us know how it all turns out. Good luck.

More reading about CSI here:

Calcium Saturation Index (CSI)

How is CSI calculated? Very simple – use our PoolMath tool. To ensure long plaster life and save money, click here to learn more.

www.troublefreepool.com

 

[Davey_crocket]

Once the drain king arrives I'll give it a crack and I also found out I can get a jet snake for my gerni for pretty cheap at the local hardware store, so two thing to try! Otherwise yea it'll be time to call in a plumber with a boroscope.

I'll keep you updated!