Poor Filter/pump Water Circulation

[atom519]

New pool owner here, so bear with me. I'm basically having problems with my pump/filter system not having much suction power as indicated by very low return water to the jet in the shallow end, and very low suction at the bottom of the skimmer.

The pool itself is old, I'd guess around 40 years or so. However, the previous owners have put in a new pump and filter since. There is no drain at the bottom of the pool, so I have to rely on the lone skimmer to gather debris off the top of the water and I manually hook up a vacuum hose to the skimmer to get dirt off the bottom.

I know that the pump itself works just fine, as when the valve it set to backwash - there is a lot of water being pulled through and I can visually see a whirlpool occurring near the skimmer as it sucks down leaves and such. However, when it's set to ANY other valve setting (Filter, Recirculate, etc) - almost no suction power occurs at the skimmer and virtually no water comes out of the return jet in the shallow end.

I got by last year by shocking often and using a battery powered vacuum for the bottom of the pool. I thought the sand filter might be the cause, so I replaced the sand this spring and just opened it yesterday to find it had the same problem as last year.

I'm looking for ideas before having a service call from a local pool company. I'm thinking the problem might be a clogged in the return line (although I would think the skimmer would still have good suction), or a broken valve somehow?

The filter is a Triton II TR50. I can take some pictures if needed.

[footie]

Which setting do you set the filter check valve to when sucking up the dirt from the bottom. You should be setting it to 'dump/waste' otherwise there is a chance that your problem might lie with bits of dibris in the check valve attached to your filter.

Just a thought.

[PoolGuyNJ]

When in filter mode, what is the tank pressure?

While B/W seems to work, how about Rinse?

Scott

[atom519]

When in filter mode, what is the tank pressure?

While B/W seems to work, how about Rinse?

Scott

Tank pressure for Filter mode is right at 8 PSI. I believe Rinse shows 8 PSI on the filter as well but don't remember off hand, can check tonight.

[atom519]

Which setting do you set the filter check valve to when sucking up the dirt from the bottom. You should be setting it to 'dump/waste' otherwise there is a chance that your problem might lie with bits of dibris in the check valve attached to your filter.

Just a thought.

I'm not sure I understand regarding the check valve. I believe last summer when I was sucking up debris with the vacuum (attached to skimmer line) I had it set to Filter. However, I only did this once or twice as it was sucking up so little there really was no point.

[footie]

I'm not sure I understand regarding the check valve. I believe last summer when I was sucking up debris with the vacuum (attached to skimmer line) I had it set to Filter. However, I only did this once or twice as it was sucking up so little there really was no point.

There is a valve that is attached to your sand filter, on it there will be six positions for the level, recirculate, filter, rinse, closed, backwash and dump/waste. When you clean the filter on a regular basis you turn the level to backwash and run the pump for a couple of minutes or so in that position before switching the level to rinse for a further 30 seconds or so. When you vacuum the pool you are meant to switch the level to dump/waste to by-pass the filter altogether, not doing it this way can cause debris to gather in this valve attached to the sand filter.

Another thing worth checking is whether the valves at the pump, you should have two (one for the skimmer and the other for the sump in your pool) are switched fully open, part closed will stop their suction ability. Also sometimes in your skimmer and below it's basket you may have another turn off valve, check to see if it's open.

P.S.

What volume is your pool and the HP of the pump?

[Beelzy]

Maybe the pump is undersized, or the impeller in it is plugged with debris??

What can you tell us about the pump?

[atom519]

There is a valve that is attached to your sand filter, on it there will be six positions for the level, recirculate, filter, rinse, closed, backwash and dump/waste. When you clean the filter on a regular basis you turn the level to backwash and run the pump for a couple of minutes or so in that position before switching the level to rinse for a further 30 seconds or so. When you vacuum the pool you are meant to switch the level to dump/waste to by-pass the filter altogether, not doing it this way can cause debris to gather in this valve attached to the sand filter.

Another thing worth checking is whether the valves at the pump, you should have two (one for the skimmer and the other for the sump in your pool) are switched fully open, part closed will stop their suction ability. Also sometimes in your skimmer and below it's basket you may have another turn off valve, check to see if it's open.

P.S.

What volume is your pool and the HP of the pump?

Correct, I was using filter setting instead of waste when running the vacuum - but again this problem existed prior to using it the first time so it's hard to say what the previous owners were using. Is it possible that only certain settings on the valve are having problems with water flow (as the backwash seems to work great)? I'm assuming that taking apart the valve could lead to some problems trying to get it put back together correctly.

I'm not seeing any valves at the pump itself, or anything that looks to be half open/closed. I don't believe there is any valve below the skimmer either, simply one line down at the bottom.

I believe the pool is 10k gallons. The pump is a Centurion .5hp, I'm not sure on specific model number but could look. I originally thought the pump was to blame, but since the backwash works so well - I started to believe the problem lied elsewhere.

Here is a picture of the filter/pump (disregard top of the filter, I was replacing the sand): http://dl.dropbox.com/u/3714475/IMG_1675.JPG

[footie]

The only reason I mentioned it was my pool guy said it sometimes happens when you vacuum on filter mode. Also you say that you don't have two pipes that tie into one prior to entering the pump?

Another thing 1/2 hp sounds to be boarderline for this size of a pool, personally a 3/4hp pump would be better.

Anyway I hope you get it sorted.

[Beelzy]

Unless the pool is right next to that equipment setup, that motor is TOO SMALL for that old Bronze pump.

I'll even wager that there is still a 1.0 or 1.5 hp impellar on the end of the motor shaft too!

[atom519]

Unless the pool is right next to that equipment setup, that motor is TOO SMALL for that old Bronze pump.

I'll even wager that there is still a 1.0 or 1.5 hp impellar on the end of the motor shaft too!

It is indeed right next to it, if that makes a difference. Probably 1 foot to the right of that picture.

[footie]

Was just looking at your picture of the check valve at your sand filter, looks to be the same as my own though my filter has a glass dome with the pressure gauge of top. I noticed no valve going to the pump, I'm guessing the reason I might have them and you don't is because my pump is below the water level but still you should/need some way of adjusting the amount of flow between your sump and skimmer/s, generally the skimmer should have more flow rate than the sump. Maybe my setup is overkill because it was installed by the guys that install commerical pools but I can vary the rate of everything in my pool.