Skimmer questions

[ojlaw]

hey all, new guy here. after an algae outbreak a couple months ago and my pool tech having trouble getting it under control i decided i couldn't do any worse myself so here i am. i bought a TFP test kit a couple weeks ago. i had the pool water reverse osmosis filtered yesterday because a lot of the levels were too high for the TFP method. i bought the house / pool about three years ago but the pool was built in the early 80's. i've been reading everything i can on TFP for a couple months, y'all are awesome and made it an easy decision to tackle the pool chemistry on my own. that's my quick intro...

while here, the filtering tech was playing around with the skimmer diverter (removable plastic piece in bottom of skimmer) and when rotating the diverter the suction on the skimmer never changes as if the diverter isn't doing anything. something i've noticed too, however, i didn't fully understand what it should do. he mentioned it should act to bypass the skimmer and suck more water from the main drain. i plugged the skimmer entirely and the GPM on the flowvis dropped to nearly 0. so the question i have is, does that mean the main drain in the deep end is not sucking any water?



i have attached a couple of photos. if you zoom in on skimmer 1.JPG you can see the where the pipe on the right in the bottom hole is the suction that goes to the pump. below that the plumbing continues down for a couple inches and appears to stop. you can see some sand collected in the very bottom. is that typical or does that plumbing normally continue? the pump was running when i took the photos, the sand never goes away.



other photos -

thanks in advance for any insight here!

 

[1poolman1]

If you look closely, you will see that the pump port is in the side of the pipe. The main drain should have been connected to the bottom port that does not appear to have ever been opened. The markings on the bottom are index marks to let you know where the diverter is placed. The diverter should or did have a small "arm" that fit under the index plate.

 

[ojlaw]

Thanks, So in my case the diverter isn't doing anything since the bottom port to the main suction drain isn't opened?

 

[1poolman1]

Thanks, So in my case the diverter isn't doing anything since the bottom port to the main suction drain isn't opened?

That's what it looks like from 500 miles away, yes.

 

[Jimrahbe]

oj,

Most pools do not need a main drain at all. It surely had nothing to do with you getting algae.

I have two rent house pools that have not had an operating main drain for over 10 years and they work just fine.

I would not spend another 5 seconds worrying about it.

Thanks,

Jim R.

 

[HermanTX]

Just to confirm - do you only have 1 pipe connected to the suction side of the pump? Maybe post a picture of your pump and equipment pad.

 

[ojlaw]

oj,

Most pools do not need a main drain at all. It surely had nothing to do with you getting algae.

I have two rent house pools that have not had an operating main drain for over 10 years and they work just fine.

I would not spend another 5 seconds worrying about it.

Thanks,

Jim R.

thanks. the algae was caused by high CYA and low FC in my opinion. the pool tech kept throwing algaecide then PoolRx copper, which helped once i kept the chlorine at a suitable level for the amount of CYA. the blond kids with green hair are nice because i'm a bit punk rock like that and i could have a laugh at them. however, reading here there are other ways to deal with algae than having green hair because of the copper.

mostly i am the curious type so i'm trying to figure out why i have a main drain if it's not doing anything. i hadn't thought of the skimmer drain plumbing today until the filter tech asked about the diverter today.

@HermanTX i will post pictures of the plumbing at the pump later to confirm.

i really appreciate all the quick responses!

 

[ojlaw]

here is a picture of the plumbing at the pump. on the pool side suction coming out of the ground are two pipes, there is one 1.5" pipe that Ts into a 2" pipe, then to the valve that switches to suction to spa side

 

[HermanTX]

here is a picture of the plumbing at the pump. on the pool side suction coming out of the ground are two pipes, there is one 1.5" pipe that Ts into a 2" pipe, then to the valve that switches to suction to spa side

View attachment 433148

Interesting because there is no valve between the 1.5” & 2” Tee on the pool side suction. Do you have 2 skimmers? You mentioned earlier that you plugged this skimmer and the flow went to zero. Any thought of what that other pipe is coming from?

 

[ojlaw]

Interesting because there is no valve between the 1.5” & 2” Tee on the pool side suction. Do you have 2 skimmers? You mentioned earlier that you plugged this skimmer and the flow went to zero. Any thought of what that other pipe is coming from?

i only have one skimmer. i’m thinking that skimmer goes to the 1.5”pipe at the pump. i’m thinking the 2” pipe at the pump goes to the main drain suction but it’s blocked somewhere. that’s why when i plug the skimmer the flow drops to zero. but i certainly welcome any other thoughts from more experienced people. i haven’t even considered the main drain being blocked before today. as Jim R. mentioned it’s not a big deal. but now i’m curious.

 

[HermanTX]

i only have one skimmer. i’m thinking that skimmer goes to the 1.5”pipe at the pump. i’m thinking the 2” pipe at the pump goes to the main drain suction but it’s blocked somewhere. that’s why when i plug the skimmer the flow drops to zero. but i certainly welcome any other thoughts from more experienced people. i haven’t even considered the main drain being blocked before today. as Jim R. mentioned it’s not a big deal. but now i’m curious.

Well I feel the early discussion was about the skimmer and the main drain was not connected to it and the diverted valve was of no consequence. But now if that 2”pipe is the main drain, then it must be blocked if you were able to block the skimmer effectively and had no suction to the pump.

I think if main drain is blocked, you just need to be concerned about never letting your water level drop below the skimmer when the pump is on or you will possibly cause damage to the pump.

Maybe others have other views.

 

[Jimrahbe]

oj,

I have a rent house with what looks like the skimmer that you have. Just one hole in the bottom. It is also obvious that at one time it had an adjust system in the bottom that was long gone before I ever bought the pool.

I know for a fact that my main drain is plumbed into the bottom the skimmer and the suction from the pump is also plumbed into the bottom of the skimmer. If I put a rubber ball over the suction hole in the bottom of the skimmer, my pump will start drawing water from the main drain. I need a skimmer all the time and I never need a main drain, so I just leave it the way it is. I see where yours does not do this, but your skimmer may be plugged on purpose.

Since there was at one time a device that allowed you to adjust the amount of water coming from the skimmer or the main drain, it makes sense that the main drain has to be plumbed into the bottom of the skimmer. It is the only logical answer.

Thanks,

Jim R.

 

[ojlaw]

oj,

I have a rent house with what looks like the skimmer that you have. Just one hole in the bottom. It is also obvious that at one time it had an adjust system in the bottom that was long gone before I ever bought the pool.

I know for a fact that my main drain is plumbed into the bottom the skimmer and the suction from the pump is also plumbed into the bottom of the skimmer. If I put a rubber ball over the suction hole in the bottom of the skimmer, my pump will start drawing water from the main drain. I need a skimmer all the time and I never need a main drain, so I just leave it the way it is. I see where yours does not do this, but your skimmer may be plugged on purpose.

Since there was at one time a device that allowed you to adjust the amount of water coming from the skimmer or the main drain, it makes sense that the main drain has to be plumbed into the bottom of the skimmer. It is the only logical answer.

Thanks,

Jim R.

thank you, this seems reasonable. i am curious how the bottom of the skimmer would be plugged. by the looks of it, it is the original skimmer as the concrete all around it looks like the original old deck concrete. so i'm not sure how the skimmer would be plugged in the vertical pipe at the bottom of the skimmer. it's hard to see in the picture but the bottom of that tube where the sand is sitting is more of a pure white as opposed to the skimmer plastic which is off white. additionally it is concave and the sand settles towards the center. it kind of seems like a PVC cap that was put on from the outside.

next time i pull the cover i'll dive down to the deep end and see if the main drain is getting any suction.

any thoughts on what the two lines are coming out of the ground at the pump on the pool suction side?

 

[Jimrahbe]

any thoughts on what the two lines are coming out of the ground at the pump on the pool suction side?

oj,

I have no idea.. I can't think of anything that would not have a valve to turn it on or off.

Let's ask @JamesW as he knows... just about everything. Maybe he knows more about your specific one-hole skimmer.

Thanks,

Jim R.

 

[JamesW]

Try pushing water into the pipe to see where it goes.

 

[ojlaw]

well here is one reason the flow drops to zero when the skimmer is plugged. this is after i vacuumed out what is the main drain

 

[HermanTX]

well here is one reason the flow drops to zero when the skimmer is plugged. this is after i vacuumed out what is the main drain
View attachment 433555

Is that plaster? seems they did not do a good job of keeping the drain covered when plastering.

 

[ojlaw]

Is that plaster? seems they did not do a good job of keeping the drain covered when plastering.

kind of looks like plaster. here is a chunk that was in there that the vacuum didn't pick up. i broke it to see the cross section. the thing is the drain cover was easy to take out with the screws, you can see the ring and the 4 screw holes where the drain cover sits. so if they plastered in there did they just leave the drain cover on and clean up around the edges? i don't know the history so it seems like kind of a risky move to break the material out if it was placed there on purpose.

 

[HermanTX]

kind of looks like plaster. here is a chunk that was in there that the vacuum didn't pick up. i broke it to see the cross section. the thing is the drain cover was easy to take out with the screws, you can see the ring and the 4 screw holes where the drain cover sits. so if they plastered in there did they just leave the drain cover on and clean up around the edges? i don't know the history so it seems like kind of a risky move to break the material out if it was placed there on purpose.
View attachment 433570

They normally plaster without the drain cover but they put a rag in the drain to prevent plaster from settling in it and clean it up fairly quickly. It appears they did not pay much attention to this unless the plan was to block the drain on purpose. Who knows!!!

Maybe some others will have ideas.

 

[ojlaw]

another question, and this one relates to the topic again my skimmer has never had a weir door. sounds like this is a good thing to have. i cannot find any info on the skimmer or lid about who manufactures the skimmer. the skimmer has a pin on each side to hold the door (see picture). the skimmer opening measures 8.25" wide by 6.25" tall. does this door look like the correct replacement for the pins? thanks for all your help.