I am a new pool owner (just moved) and have been reading this site for some great info.
The previous owner was using trichlor tabs in a floater, and when I measured the CYA it was >100, so hard to tell actual level as the scale on Taylor kit does not cover the level I see. It may be as high as 200 based on a guess of the level as it seems to be logarithmic but not sure how accurate in that range the kit is.
I just plumbed in a SWG and hooked up to my timer, but before adding chemicals (salt, borax, acid) I was planning to drain about 50% of my pool. However, I can only drain about 2 feet below my skimmers. Let me give more details about my pool and problem:
In ground, guess about 24,000 gallons
One pump for filter (DE)
One pump for polaris pool sweep and I think also connects to skimmers
Each pump has separate intermatic timer
Booster for spa (seems to just make air bubbles)
One main drain in deep end
Two drains in spa
Return line to spa separated from return line to pool (valve can select the path)
Suction line from spa separated from suction from pool (valve can select the path)
My problem: I cannot drain my pool any more than about 2 feet below my skimmers
I set my DE filter to backwash, I connect drain hose to this and can drain from there
First let me may say that my spa can drain perfectly fine, the pump is primed and it drains fast.
So when setting suction line to come from spa, everything works.
Now, when I start draining my pool, it works fine until I get below my skimmers.
When water line gets below skimmers, the pump loses prime, as I see air, but still has enough pressure to continue pumping, albeit at a much, much slower rate. It pumped until the water line was about 2 feet below the skimmers, then it could not pump anymore.
During this slow pumping phase, I could hear air gurgling from one of the skimmers.
I am new to pools and did not know there could be any plumbing connection on this skimmer to the main drain, but upon searching I just found it is usually the case.
So it seems air is getting in through skimmers?
The skimmers do have diverters.
On the bottom of the diverter is a small swivel door that can close a hole on bottom, currently they are open.
I tried closing but does not make a difference.
Both skimmers have two holes in the bottom below where the diverter sits, both open.
During the slow pumping phase, one of the holes on both skimmers can have suction when the pump is running, but sometimes water will also squirt out of this hole.
Also, where the diverter sits on top of the skimmer, there is an O-Ring. On one skimmer, this O-Ring has expanded, it is not making a good seal.
Where do I buy replacement O-Ring and could this be the problem?
Should I plug all these holes in the skimmer when draining, if so where is best place to get the plugs?
Thanks in advance!