SF = service factor. There is a nice description of that here: understanding-pump-service-factor-t1366.html
I checked out my "2HP" WhisperFlo and it pulls 11.0A at 220V, which would be roughly 22A at 120V. I'm going to suggest that you stay with 220V to wire up the pumps. Yes, 2P 220V breakers are expensive, but not much more than two separate 1P breakers. I picked up a 2P 220V 20A breaker from Murray for $65 at HD (online, actually since they didn't have one in a nearby store). That's the best price I could find online. You might check to see if that is compatible with your Square D sub-panel.
I recently set up a sub-panel with a 60A line run from the main panel. It has 2 220V/20A GFCI breakers, one that feeds the filter pump and NG heater, the other feeds a 2HP waterfall pump. The panel also has additional 15 and 20A breakers for various circuits. While it would be best to have independent breakers, you may not have space in your current sub-panel. It's also a little surprising that they only pulled a 20A 220V line to your pad, but with everything on, you are pretty close to the 75% I described earlier so it should be okay.
Bonding should be different from equipment grounding. As you know, bonding ties the pool's structure and nearby deck together to the same potential. Bonding wires usually are terminated at the equipment pad via bonding lugs on the pump, heater, etc. This is in addition to separate equipment grounding connectors that connect the green ground wire to the grounding bar in the panel. My read of the NEC is that the bonding grid and equipment grounding are kept separate, but this doesn't seem to be the case practically.
I checked out my "2HP" WhisperFlo and it pulls 11.0A at 220V, which would be roughly 22A at 120V. I'm going to suggest that you stay with 220V to wire up the pumps. Yes, 2P 220V breakers are expensive, but not much more than two separate 1P breakers. I picked up a 2P 220V 20A breaker from Murray for $65 at HD (online, actually since they didn't have one in a nearby store). That's the best price I could find online. You might check to see if that is compatible with your Square D sub-panel.
I recently set up a sub-panel with a 60A line run from the main panel. It has 2 220V/20A GFCI breakers, one that feeds the filter pump and NG heater, the other feeds a 2HP waterfall pump. The panel also has additional 15 and 20A breakers for various circuits. While it would be best to have independent breakers, you may not have space in your current sub-panel. It's also a little surprising that they only pulled a 20A 220V line to your pad, but with everything on, you are pretty close to the 75% I described earlier so it should be okay.
Bonding should be different from equipment grounding. As you know, bonding ties the pool's structure and nearby deck together to the same potential. Bonding wires usually are terminated at the equipment pad via bonding lugs on the pump, heater, etc. This is in addition to separate equipment grounding connectors that connect the green ground wire to the grounding bar in the panel. My read of the NEC is that the bonding grid and equipment grounding are kept separate, but this doesn't seem to be the case practically.
