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View Full Version : Too much suction !!



karenkr
07-19-2006, 01:15 AM
Hope I am posting in the right place--
Have an IG pool. have been having problems with algae so have been shocking and vacuming a lot. Problem is now I have too much suction and the vacum wont move. I have to pick it up to move to another spot. Started about 2 wks ago--before that no problem to vacum. For some reason it just wont roll. Any suggestions anyone????

tenax
07-19-2006, 07:12 AM
you say it won't roll..is this an auto vac? does it have a regulator attached to the hose that you can control the suction with? i've had that problem with both an autovac and manual. especially with the manual as it had no regulator. in my case, i've got a main drain return and skimmer return so i can simply open the main drain a bit to reduce the suction. not as convenient as a regulator on the hose. i have been considering installing a valve that allows some air to get into the vacuum line going to my skimmer (as is the case on the auto vac line) and that would work great.

tenax
07-19-2006, 07:14 AM
ps- you said it didn't happen..now it is..i'm guessing that your filter likely needs cleaning. i know with mine that when my filter is dirty, it goes from a standard 10 lb per square inch clean to 15 when dirty, which in turn creates more water pressure in the system overall, leading to stronger suction.

JohnT
07-19-2006, 07:48 AM
Hope I am posting in the right place--
Have an IG pool. have been having problems with algae so have been shocking and vacuming a lot. Problem is now I have too much suction and the vacum wont move. I have to pick it up to move to another spot. Started about 2 wks ago--before that no problem to vacum. For some reason it just wont roll. Any suggestions anyone????
Check the brushes for wear (assuming it has brushes). Once they get down so far, the head will start to stick to the bottom.

duraleigh
07-19-2006, 07:54 AM
Karen,

I doubt it's too much suction. Your flow thru the system would have to had inexplicably increased for the suction to go up.

Actually, if it was too much suction, that is easy to fix by simply restricting one of the ball valves on the pressure side of the pump. Your filter pressure will go up, and the flow thru the system will decrease resulting in less suction at the vac head.

tenax
07-19-2006, 10:03 AM
duraleigh, i'm no expert, but can only go by experience that when my filter pressures rises, my suction increases, rather than decreases. that is factual experience. i can definitely tell the suction has increased?

cwstnsko
07-19-2006, 10:10 AM
That seem counter-intuitive. It'd be like saying that your vacuum cleaner has more suction with a dirty bag than with a clean one. To have more suction, you need higher flow rate. Dirty filters cause a lower flow rate and should result in less suction

mas985
07-19-2006, 11:32 AM
There is only one condition where this can be true and that is with a 2 speed pump. Going from low to high speed, you are effectively changing the HP of the pump so you will see both a rise in PSI as well as suction.

Assuming the same pump and speed, and the PSI rise is due to a dirty filter, solar or other return restriction, higher filter pressure = more head loss which means less GPM. Less GPM = less suction. This what hydraulic theory dictates and what I have confirmed through measurements.

If you had a suction guage on your pump, you would see it drop with higher filter PSI. However, just the opposite happens when the PSI drops so perhaps this is what you are experiencing.

karenkr
07-19-2006, 09:06 PM
Ok guys ---thanks for all the input but honestely we do have too much suction. Hubby actually bent the pole trying to get the head unstuck. Also you are talking to a real dummy here. As you can guess this is our first season of maintaing our pool on our own so we have lots to learn and we sure do appreciate your help.The pump is an AquaTool Sand filter,Stay -rite
dyna Glass with RPM of 3450- tank says 300lbs. I have no idea about what I just wrote--that is just what it says on the tank. Thought maybe it might help you guys.
To vacuum we put this black disc in the skimmer and attach the hose filling it with water. The head is attached at the end of the hose that we put in the pool. Keep water pressure about 15--if it starts to rise we backwash. The only thing we have not been doing is rinsing MAYBE that is the problem!! Could the sand be too dirty? Water is dirty when backwash but clears right up in few min. Should I be rinsing after I backwash??
Duraleigh you suggested restricting the ball valves on the pressure side of the pump---How do you do this (told you I was a dummy)

Please keep the suggestions going--ALL help is appreciated

Thanks
Karen

duraleigh
07-19-2006, 09:26 PM
Karen,

You should have a valve/valves on the pipes that come out of your filter and take the water back to the pool. If you partially close that/those valves, your pressure will rise on your guage and you will have less flow throughout the entire system....that means less suction.

I'd stop closing the valve when the pressure got to 25...maybe 28 max.

NeilK
07-20-2006, 11:27 PM
With some of the pool owner's manuals I've read, if the vac head gets stuck on the bottom, it is recommended to shut off the pump. That should take care of any pole bending problems when trying to free the vac head.

A few questions.
Does your pool have a main drain?
Does your pool have 1 or 2 skimmer's?
What type of in ground pool is it? (Gunnite, Plaster, Vinyl, Tile, etc.)

KurtV
07-20-2006, 11:46 PM
Karen,
Do you have a main drain on your pool? If so, have you closed the valve on that pipe thereby diverting all the suction to the skimmer? Is is possible that your main drain has something on it or in the pipe that is keeping you from getting suction there?

karenkr
07-21-2006, 02:05 AM
Thanks everyone for your input.
Answers to questions: I really dont know if we have a main drain or not. Where might it be located? When we partially drained the pool -- just used a small pump.
Only have one skimmer
I have been told the pool is gunnite.

Boughr a new head at walmarts today--going to try that tomorrow
Again thanks
Karen

KurtV
07-21-2006, 02:13 AM
Thanks everyone for your input.
Answers to questions: I really dont know if we have a main drain or not. Where might it be located?
In the bottom of the pool.

When we partially drained the pool -- just used a small pump.
Only have one skimmer
I have been told the pool is gunnite.

Boughr a new head at walmarts today--going to try that tomorrow
Again thanks
Karen

Is there a valve or valves on the pipes the go into the suction side of the pump (the side that has the pump strainer on it)?

karenkr
07-22-2006, 10:52 AM
If I am looking in the right place-----There are 2 valves a red one and a green one. Also I noticed last night when I tried to vacuum that the pump was not holding prime (yes I did have pool level up). Could I be having pump problems?????????? I hope someone out there has some suggestions

Thanks
Karen

KurtV
07-22-2006, 08:25 PM
If I am looking in the right place-----There are 2 valves a red one and a green one. Also I noticed last night when I tried to vacuum that the pump was not holding prime (yes I did have pool level up). Could I be having pump problems?????????? I hope someone out there has some suggestions

Thanks
Karen

Are both those valves open (the handle will usually be in line with he pipe when the walve is open)? If not, your main drain valve may be closed which would increase the suction from the skimmer and might also contribute to your priming problem.

karenkr
07-23-2006, 10:47 AM
Thanks for answering me

First I was wrong on the color (dont know if it matters) One is red and the other blue not green. Duh---guess my memory is not too good.

Yes both are in line with the pipes.
Got the new head from Walmarts ---did get to vacuum last night--had good suction not too much so maybe it was the head after all.

Still worried about the prime thing--or could that be normal when vacuuming??It did return to normal when I backwashed.
Thanks so much for your help
Karen

curlysue121350@yahoo.com
07-23-2006, 10:55 AM
I had similar problem last year. the brushes on the bottom of the vacumn head were worn down. once i replaced the brushes no more sticking.

tenax
07-23-2006, 11:36 AM
karen,i find i can lose prime while vacuuming if 2 things occur:

a)my main valve is closed (so water is only going through the skimmer and hence the vacuum..so if the vacuum, or vacuum line is plugged,you lose prime) you can leave your main valvel completely open or partially if it decreases your vacuum suction too much and that way you won't lose the prime.

b) if my basket in the pump itself is full of gunk. in which case, obviously doesn't matter which valves you have open and closed or how much given it's one line going into and out of the pump!

check both of those things out. at start of season is when i tend to lose prime because the bloody basket keeps filling up with muck from the winter (leaves, sediment,little twigs,etc..hence why i'm buying a leaf cover for the fall)

karenkr
07-23-2006, 01:48 PM
Thanks
Will check both those things.

Will just keep watch on prime to make sure does not go completely dry.

Sure appreciate all your help
Karen

Razorback Fan
07-25-2006, 10:46 AM
Had same problem this summer. The vacuum would stick to bottom of pool (inground fiberglass). Called the pool installer. She said the wheel on the vacuum head are adjustable. Lower the wheels on the vacuum to raise the suction away from the pool. This worked for me, no problem since.