Stats as I know them:
Pool: 20,400 gal
Filter: new 60 sq ft Pentair DE
Max flow rate of filter: 150 GPM
Pump and filter plumbing: 2" PVC
Max Flow Rate 2" PVC: 100 GPM (Another said 73 GPM)
Pump: AO Smith USQ1102 1HP (SF 1.25) with matching 1HP impeller
feet head (as estimated by inyopools formula):
Shallow End Skimmer: 10 + 12 = 22 feet
Deep end Skimmer: 22 + 7 + 28 + 12 = 69 feet
Deep End Drain: 10 (feet deep) + 22 + 28 + 12 = 72 feet
Avg: (22+69+72)/3 = 54.3333 feet head estimated
I purchased a house and inherited pool and equipment. The pump motor was an AO Smith USQ1102 1HP (SF 1.25) motor. The motor died. I took it in to get a replacement, the pool store mentioned that the impeller was a 1.5 rated impeller. I ended up purchasing a 1HP exact replacement and a new matched 1HP impeller. Since this "fix", one of the skimmers does not work well (hardly any water movement through it).
When I clean our brand new 60 Sq Ft DE filter, the filter pressure is 9lbs and I get unbelievable water flow out the pool jets. The surface roils! However, within a short time (maybe a month), the pressure in the filter builds up to 14lbs and I get no noticeable flow through the pool. I'm sure water is flowing somewhat, but the skimmers are essentially still and the surface of the pool is calm. At this point, the pool water quickly degenerates.
Question 1 (This is not a backwash question):
It would seem to me that I should be able to push more than a 5lbs difference between clean and fully dirty filter.
If I move from a 1 HP motor to a 1.5HP motor (with matching impeller upgrade), would this allow me to push more through or would it just bump up all the pressures and I have the same 5lbs difference?
If an upgrade is a good idea, what is a good pump motor/impeller combination? The whole (feet head + service factor + xxx) leaves me dizzy.
If an upgrade is a good idea, is there any benefit to replacing the pump housing/filter basket? I'm not a fan of the spin off lid that I have now... I'd like a lid that is easier to remove and attaches/seals easily.
Thanks in advance for your thoughts (especially on Q1).