Skimmer suction

epxroot

Well-known member
Jun 7, 2012
163
0
#1
My skimmer has little to no suction on it. First time pool owner and just opened the pool up this weekend. Seemed like everything was working fine at first, I was able to vacuum the pool with no issues. After that first day I wanted to vacuum again after the pool party we had for my son the day before, lots of sand a on the floor. Hooked up the vac, and nothing. Checked the skimmer, there was very little suction. I remember the day before it had a little swirl and was slowly pulling things down into the basket. I turned off the pump and checked the basket there. Well it was very dirty. I cleaned it out popped it back in and started the pump back up and started to vacuum again. I was doing OK for a bit, but then it just stopped picking up again. Decided I was going to stop and try to figure out what was going on. Started to pull the vacuum hose out of the pool, and lost most of the sand that I sucked up, fell right back in the pool out of the vacuum hose! One thing I noticed is if I stop the pump and restart it, there seems to be a little suction at the skimmer, but it slowly fades to next to nothing. Any ideas?
 

zea3

Mod Squad
LifeTime Supporter
TFP Expert
Jul 10, 2009
10,860
0
Houston, Texas
#2
Here are some suggestions for troubleshooting:
Check the hose for blockage. Take the disconnected vacuum hose and lay it out on the ground. Try to pass a garden hose through the length of the vacuum hose dry. If you meet resistance connect the garden hose to a faucet and continue trying to pass it through the vacuum hose with the water running.
Has the pressure on the filter risen by 10% or more or is return flow into the pool is weaker since the last time it was back-washed? If so try back-washing the filter.
If neither of these is the problem, there could be a blockage between the skimmer and the pump. To check open the pump basket and run the garden hose through the line from the pump basket to the skimmer with the water running. Any debris should be flushed back into the pool. If you find a blockage in the line that cannot be cleared with the hose you may need to get a "drain king" for the hose that forms a tight seal inside the pipe to use pressure to clear the blockage. Let us know if any of these help.
 

epxroot

Well-known member
Jun 7, 2012
163
0
#3
The vacuum line is new, but I will check to see if anything is blocking it. The pool has been closed for a few years and I just opened it this weekend. I did a backwash/rinse a few times before adding Cyanuric Acid to raise my cya. The pressure dropped after backwash, but the water never ran dirty. I will not be abe to backwash until I do a cya (I believe it can take up to a week to read) test toward the end of the week. I will try running the garden hose through the plumbing back to the skimmer to make sure there are no blocked lines. I noticed I have to valves on the intake lines. I am assuming one is for the drain at the bottom of the pool and the other is for the skimmer but I am not sure which one is which. Plus I am not sure if I can make the turn into the T fitting. Is it possible to turn the pump off and run from the skimmer back to the pump?
 

epxroot

Well-known member
Jun 7, 2012
163
0
#4
Could the actual problem lay within the pump itself? It is an old pump from what I know, and the pool guy said that it was on it's last leg.
 

lightingguy

LifeTime Supporter
Jun 18, 2010
513
0
Glendale, CA
#5
Just to confirm - the Pump Basket was filled with leaves and other largish material? If that is the case - it's possible that there is a blockage in the piping from the skimmer to the pump.

That would explain the brief suction you get after pump shut off - there is a clump of leaves trapped on a stick or something. They loosen when the pump turns off and float upstream a little. You turn on the pump and there's flow until the blockage fully reseats itself.

There are things you can do to try to clear the blockage - but if the pipes are underground there is no sure fire solution.
 

epxroot

Well-known member
Jun 7, 2012
163
0
#6
Yes, the basket at the pump was bad. The ribbed walls on the basket were covered with debris all the way around. It took about 10 minutes to get it cleaned out. I also read I should check the impeller. The pool guy had the pump open but he may not have checked this, or it could have become clogged after he closed it. The pump ran for a good 30 to 36 hours before I cleaned out the basket at the pump.
 

lightingguy

LifeTime Supporter
Jun 18, 2010
513
0
Glendale, CA
#7
If you have reason to believe that someone has done bit of vacuuming or large debris (leaves, etc) without a leaf basket - then you most likely have some sort of blockage in the pipe run from skimmer to pump.

If that's the case you can try something like a "Drain King" to inject pressurized water backwards through the pipe to try to clean it.

Internal blockages can be tough to clear
 

epxroot

Well-known member
Jun 7, 2012
163
0
#8
I tried the garden hose which came through the other end but slightly. May not be enough pressure from the garden hose to really do anything. I suspect something is in there because I keep finding these little stick like things in the pump basket that I know have not been falling into the pool, and even if they were, I don't have enough suction to pull much of anything down into the basket.
 

epxroot

Well-known member
Jun 7, 2012
163
0
#9
Another thing I found out was that both the main drain and skimmer line were fully opened. I tried closing the main drain some to see how it would impact my skimmer line. There was a difference but it still wasn't pulling the insect down into the skimmer basket even after I closed the valve to the main drain completely. Once I opened the main drain up some I started getting bubbles coming out of my return line in the deep end of the pool. I fully opened the main drain valve but the bubbles kept coming out. I shut the pump down, powered it back up and the bubbles stopped. Any idea why when the main drain valve is partially closed I get bubbles out of the return in the deep end?
 

lightingguy

LifeTime Supporter
Jun 18, 2010
513
0
Glendale, CA
#10
IF your skimmer line is blocked and you close off the main drain there are two possible sources of air bubbles. 1 is a suction side air leak that is only visible when the flow from the pool is severely restricted - the other is cavitation inside the skimmer line (restricted flow causing air bubbles to come out of the water).

Either suggests a skimmer line blockage and not something wrong with the pump - sorry to say
 

epxroot

Well-known member
Jun 7, 2012
163
0
#11
Thanks for all the replies. I will try and get a drain king or a drain jet, something that would have a little more pressure than just a garden hose. Is there anything I need to be concerned with when using either of these to try and unclog the possible clog? If that doesn't work would it be possible to try and snake the line? It should all be 1 1/2" Schedule 90 PVC so there shouldn't be a whole lot of concern snaking it.

I am almost convinced there is some kind of build up in that line that isn't totally restricting the flow. I did find a piece of paper in the pump basket that I picked up when running the vac. My pool guy doesn't seem to think it is clogged since it was winterized and there was a freeze plug in the skimmer line. I am just wondering if something got in there before the plug was in, or if someone crammed something in there after it was put it. It is a repo house.
 

epxroot

Well-known member
Jun 7, 2012
163
0
#12
This is now getting a little frustrating. I figure that I either have a serious clog in my skimmer line or, my valve is not opening as it should. I took lightingguy's advice and bought a drain king, stuck it in my skimmer line from the pump up to were the line 90's back into the ground, turned it on, heard it doing it's thing, and waked over to my skimmer, there was nothing happening. All I could see was just a little bit of water making it up through my skimmer line because debris would float over and be slowly pushed to the top. Stuck my hand in the skimmer to see if I could feel any water movement and here was nothing. I am thinking about buying a valve, cutting the ole one out and checking to see if it is opening the way it should, if it is then I will try to slide the drain king in from where I cut the valve out, and try again. Any other ideas I could try before cutting the valve out?
 

Smusgrave

New member
Jun 7, 2012
2
0
#13
Valves should be able to come apart without removing the body. That should allow you to see if there's debris stuck or the valve internals are functioning. I've dealt with various types of valves having issues between the handle and ball/gate/plug/etc in industrial use and some are intermittent. If you do find the valve broken internally you may be able to buy an identical valve and drop the internals into the old body if it's in good condition and save some effort on cutting.
 

epxroot

Well-known member
Jun 7, 2012
163
0
#14
Thanks Smusgrave, that is a good idea! I believe it is a gate valve, but I am not sure if it is opening all the way. The handle spins as if it is opening but I can't say for sure it is. Have you ever ran into that issue? Where the handle will spin but the valve stays partially closed?
 

lightingguy

LifeTime Supporter
Jun 18, 2010
513
0
Glendale, CA
#15
It's unlikely that you can turn the handle but the gate doesn't move - it is easy to check though. Turn it so the handle points to the main drain pipe - this should block off the skimmer. You should get good flow. If you turn it so the handle points to the skimmer - you are now blocking the main drain and probably have flow problems.

If you do take the valve apart - it will be a good idea to have a replacement set of o-rings and a tube of silicon lube handy. If the o-rings are old they can disintegrate when you pull valve apart.
 

epxroot

Well-known member
Jun 7, 2012
163
0
#17
Thanks everyone, I will try and get a pic when I get home from work. My pool guy still thinks it's the pump and filter, which I don't understand. I would think if it was the pump and/or the filter, I would have the same effect on both my Skimmer and main drain line, but it doesn't. Skimmer closed and main drain open, full prime and no air. I open skimmer line and air starts to come in. Close main drain and fully open skimmer, I get maybe 3/4 prime and lots of tiny air bubbles out of my returns. I do not believe it is a leak in my skimmer line since my pool has had the same level of water for the last 4 days. I feel convinced something is in that line!
 

epxroot

Well-known member
Jun 7, 2012
163
0
#18
I spoke with the company who installed the pool and they use polypipe for underground plumbing. So now I have one more thing to add to the list of things that could be why I am not getting good waterflow in my skimmer line. I also noticed a small leak from the handle on my valve on the skimmer line.
 

epxroot

Well-known member
Jun 7, 2012
163
0
#19
Sorry, didn't get any pics uploaded last night. I spent the night doing some digging, some drain kinging, and some snaking! Last night I ran the drain king again for about 10 to 15min letting pressure build and then release it with my freeze plug. I snaked 20' (length is only about 25') of the line and found no resistance int he line. I am now just going to work my way back from the pump to the skimmer. Tomorrow I plan on replacing all the plumbing above ground at the pump (it's been there for 17 years) which includes fittings, the old gate valves, and my O Ring on the primer basket, and I think I am going to put a union in at the pump since I plan on replacing the pump this year or next. I noticed last night as I was messing with the pump and valves that my pump was not getting prime and as soon as I touched the skimmer valve it suddenly started pulling a prime. I also noticed a little bit of water coming out of the handle on the gate valve connected to my skimmer line. I really don't have $100 to drop on two valves at this time, so can anyone recommend any decent valves to use, would Lowes or Menards carry any?
 

epxroot

Well-known member
Jun 7, 2012
163
0
#20
Thank you all for your help! I finally whooped it. Replaced all the plumbing on the suction side above ground. I am now running at full prime on both main and skimmer with no pressure drop when switching from one to the other!