Low Pump Pressure (5 psi)

[mak8409]

Pump pressure is consistently low, around 5 psi. Although when I went to vacuum yesterday it was up at 30, but after backwashing pressure went back down to 5. I have a great swirl of water under the pump basket lid, but no swirl at the skimmer/return at the pool. Wife said pump was also very hot when she touched the pump after seeing the 5 psi reading last night when putting on the pool cover.

Took pump to local shop. No grinding noise, metal shavings, or unusual wear. Thinking an air leak between the pump and impeller, I replaced internal rubber washers and such ($25), hooked it back up, and still 5 psi. No leaks under the basket or impeller. I asked if there was a washer between the basket and impeller, but was told no.

Could this be something other than an air leak? How much water can be circulating at such low pressure?. I have a very simple system with limited piping above ground including this Pent-air Challenger pump attached.

Any ideas?

 

[mas985]

Lower than normal pressure usually indicates either a suction pipe clog or an impeller clog.

 

[mak8409]

...a suction pipe clog or an impeller clog.

I guess I could snake the line from the skimmer up to the pump basket to see if there is any debris, frogs, or birds blocking the free flow of water up to the pump.

When you say impeller clog do you mean actually in the impeller housing, between the basket and impeller, or in the tube between the impeller and sand filter?

 

[Sminor]

You said you had high pressure while you vacuumed? Is it a suction side vacuum that hooks up to your skimmer?

 

[mak8409]

Actually I had high pressure before I vacuumed. The pressure dropped to 5 psi when I back washed before I vacuumed. While vacuuming there was just enough pressure to keep the broom on the floor bottom and suck up the little bit of debris. Yes, suction side vacuum that hooks up to the outside hole in my skimmer. Last and previous years psi was always 10-15 to 25-35 when time to backwash. First year we've had these low pressures.

I just turned the pump back on and it's about 7 psi now. I felt all the pipes and I could feel the rush of water from the pump into the sand filter, but the pipe leading from the filter back to the pool didn't feel the same way. Could there he something wrong in the sand filter? Took off the gauge as part of winterizing, but I'm changing it anyway to see if I get the same readings.