Our IG pool is approx 95% complete. We've got a meeting scheduled for Thursday with our builder for pool school and I wanted to shoot a few questions past you guys so I'd know how concerned I should be about these issues.
Pluming Configuration: (I can provide pictures upon request)
Our pool has 2 skimmers, 3 return lines, and a 4th return line that powers a Polaris 280 via a booster pump. The booster pump T's off of the main trunk line exiting the SWCG cell, which also feeds the 3 return lines. There is no isolation valve for the Polaris line so with the main pump on HIGH sometimes the polaris creeps around the pool at very low speed. The main pool pump, 1HP Hayward Super Pump 2-speed, achieves prime quickly and displays minimal bubbles in the leaf basket window.
The problem if it's actually a problem is that 2 of the 3 return lines burp bubbles. It resembles soda fizz and occurrs with a pulse-like intermittent frequency. You can also hear it if you're close enough. Again, there's minimal air in the pump window so I don't think the skimmers or skimmer lines are sucking air. Can air get trapped in the filter over time? I've programmed the main filter to shut off between midnight and 5am to save electricity. I wonder if the entire pump/filter/heater system is draining overnight and trapping air. If that's the case then I'm not concerned. I just want to make sure this isn't a harbinger of a more expensive problem.
My other question is regarding evaporation rates. Last Wednesday I noticed the level of our pool had dropped to below the screw on the skimmer box we were instructed to target by our PB. I added an inch of water that night and got the water level about 1cm above the screw. By Sunday evening I noted that the level had returned to it's previous level below the screw. The weather over the weekend was Clear/Dry/Windy with highs in the mid 70s and lows in the 40s. I don't see any obvious signs of bubbles indicating a leak but 3/4 to 1in in 4days seems like too much to just be evaporation. Note: we didn't swim this weekend so zero splash-out. Not sure of the surface area of my pool as it is freeform but the outside dimensions are approx 22x36. What kind of evaporation rates are you guys seeing this time of year? Should I insist on a leak check?
Other than these two concerns I think the overall build went pretty well and I'm prepared to cut him his final check. Please speak up if you have reservations or suggestions! Any advice would be greatly appreciated.