Good outflow, low suction...

[valuator1956]

I hope someone can help me with what I consider a weird problem. Inground pool, 1 1/2 hp pump, sand filter. I just returned to my vacation home and needed to vacuum the pool. (vacuum through the skimmer opening) In the past I have had good suction. Now I have very little suction. I have no separate inline valves controlling the bottom drain and skimmer...both connect to each other under ground and a single line runs to the pump input. So the only way I have to draw suction only from the skimmer is to cover the bottom drain. I tried covering it with a upended five gallon bucket and that seems to work fairly well. (the bucket is sucked down to the bottom). But the suction does not increase at the skimmer. In addition, I see no decrease in the outflow. How can it be that I can effectively cover both bottom drain and skimmer openings and still have outflow? I can't make sense out of it... seems like it has to drawing water from somewhere else in the pool. But where?

Bob W

 

[mas985]

What about filter pressure with and without the cleaner attached?

You only have the skimmer and main drain on the suction side?


Any air in the pump basket?

 

[OldPoolMan]

Maybe try a larger size bath mat to cover the MD.

 

[valuator1956]

Filter pressure is 20 # with and without...this is after a backwash. Only a skimmer and main drain on the suction side (which is what is making me crazy!)

There is some air in the pump basket, which has been pretty common since I bought the property 5 years ago.

I intend to replace the existing filter (sand) with a DE. I am thinking of using the existing pump to test all the lines after i have everything disconnected for the filter replacement. Just use some flex hose to draw straight from pool and then temporarily connect output to both sides and check the flow.

Bob W

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To Old Pool man...

That is a good idea. that could easily provide a better seal than the upended bucket. Thanks

Bob W