I've read everything here, I got a lot out of the School, the pinned thread, the james-m post, among others, and I've watched all the videos posted and others I could find. I think I'm close to knowing what I need to do to get it "right". I'm in Charlotte NC so chance of a freeze is relatively low but not zero and I'd rather not worry at all. However, I'm stuck on details, so sorry this is so long. Hopefully numbering the questions makes responding easier and doesn't make me seem crazy. I might be at this point...
Also note I closed my pool alone last year (not long after buying the house) and then I only blew out the returns (at that, a few weeks after blissfully closing the pool without even doing that). I don't *think* anything went wrong last winter. Removing the salt water chlorine generator (SWG) and lowering the water level below the returns I could use a shop vac to blow the water out of the returns, cap them and put antifreeze in there from the pump-side pretty easily (although after reading a lot more, I probably didn't put enough). The vinyl cover did shrink a bit (had to stretch it out and use some pennies to hold it but seems back to normal now), so I think I will re-fill the pool this year back up to closer to within a few inches of the skimmer (8 inches or more higher probably... I am on well water so will probably do it over a few days; I assume days won't matter) and then manage the water after larger rainfall with a sub-pump to keep it below the skimmer (but not let the liner dry up). I have a safety cover, so easy to peek and pump. Question 1. Does this sound right on the return side? Am I missing anything? Actually question 1.1: the water level is currently just below the skimmer. What do people think about the one-way valves? I don't think I could get my wife to work well with me to close the valve with a real cap while under pressure, so I'm leaning towards the above process to keep the peace.
This year I want to blow out the intakes properly, however I'm a bit confused. I bought a compressor to also do the irrigation lines (paid someone to do that last year, slightly less than the cost of the compressor) so I'd like to do it with that and hopefully not have to also buy a Cyclone as well (and I'm not sure it would work, see below). On the first day (this year about a week ago) I tried to run the compressor connected to the pump drain in the basket area, but was nervous about pressure in the system but went up to about 30 psi out of the compressor... The multi-port valve was on recirculate due to some video I had seen (the one linked to here on the thread by swampwoman, actually, but before I signed up here). With this setting (and the SWG connected back up on the return side) no air was coming out of anywhere... but I also don't think I waited long enough. I was running out of time that day, so I put the cover on and went back to the Internet to read up. I now know I need to wait longer, keep pressure levels at about 25-30psi (I was guessing, which is why I didn't want to trust my guess for too long) and, for the main-drain and skimmer (there's only one) put the multi-port valve on the pump to closed so I'm focusing the air on that side. Question 2: generally, am I right? 2.1: if it worked last year, does anyone think I'm crazy to bother?
My main concern is about making sure I'm not over-pressuring the system because I'm a bit confused about my plumbing... there are no 3-way valves (jandys?)... Here are the intakes:
To my understanding the valve coming out of the pump coming right out of the ground (to the right in the photo) MUST be the main-drain. The side pipe out of this (to my understanding, to the left in the photo) must be the skimmer... I can turn off the skimmer, but not the main drain (by itself, which makes sense I think, the other way around does not). However, during pump run time, I've tried to do this (close the skimmer (valve on the left in the photo like you see) and have the main drain open (valve to the right parallel to the pipe)) and to me it looks like there is still pressure emptying the skimmer (!?). Despite this (which could be an illusion) I still think my understanding of those valves/pipes is the only thing possible. I have no way of reaching the pool builder so that's out. Question 3: does everyone agree with my assessment of the plumbing? (I guess I'll find out with the process below but doubt is why I'm posting)...
Another problem is that the pump is a good 3 feet below the pool (hard to see scale but):
so when I open the main drain valve, water flows in to the pump (and in to the compressor). Nothing I can do about this water? Also, this means there is no way that I can think of to use a cyclone or the shop-vac to blow out the intakes, (question 4) is that right?? Is this a common pool setup, out of curiosity if anyone knows? With the intake valves the way they are, the valve going in to the pump is a single point of failure for the whole pool which seems like a bad idea in designing a pool.
So the process I plan on following is something like:
- connecting compressor to basket-side of pump. Pre-load compressor, leave the output closed for now.
- changing filter MPV to closed. Leave in other plug in the pump on the pump side.
- opening both valves in top photo (water will come in)
- quickly turn on compressor to about 30psi (this pressure should be ok, right?)
- this should force most air through the skimmer (I think, since that line should be shorter: skimmer is just off to the right of the pool in the second photo, deep end (~6ft) is closest to the pump, with main drain (2 intakes) at the bottom). There is no way to force all air in to the skimmer due to the crappy plumbing options, right? (question 5: a 3-way valve would be nice!)
- once all air is out of there (shop vac up the excess), close that, installing gizmo on the valve closer to the pool and the cap on the other opening.
- close valve to the skimmer. No way to get antifreeze in there? (question 6)
- Now all air should be forced to MD. Let that run for a few minutes.
- close the main-drain valve to make the air lock (from pump straight to the ground in first photo) and then turn off the compressor right away (or quickly turn MPV to back-wash to force air through the sand to clear out more water there? Seems reasonable but I've seen this poo-poohed as well).
- silly detail: with a sand pump, SWG, do people usually take everything inside? SWG, cap on bottom of sand filter, two plugs from pump, etc.? Or do any of these caps/plugs need to be left on? I just duck tapes the SWG entries... can I buy caps for this? Or in NC, leave SWG out?
Any thoughts on this process, or anything I've said here?
Apologies for being so long, but as I say I'm really getting mired in the details.