Just recently I noticed more and more air bubbles developing in the filter basket connected to the pump housing. It finally got to the point where the pump would not prime at all. First thing I tried was to inspect the pump impeller for any debris. Not much there, cleaned it and put it back. Made no difference. Next I changed the basket o-ring and cover, greasing the o-ring well. This helped a little but not much. I tried the water hose test on all the suction line connections, valves, filter basket etc. with no visable change in the problem. My set up on the suction side consists of one Skimmer line and the Main drain line. I experimented with both suction lines fully opened, then Main drain line shut with Skimmer line open, and then Suction line shut with Main drain open. No success with any of these operations. My thoughts after this was that if one of the suction lines between the pool and its shut off valve was sucking air the problem should show up only whith the leaking line flowing and the other shut, which didn't happen. So I decided that since the suction side piping and valves had been there for almost 40 years it was time for a change out anyway and maybe the problem was in the set up itself. I then removed the piping and valves and was left with both suction lines sticking up just above ground level, and the suction line on the filter basket open. I made a temporary connection isolating the filter basket line and the Main drain, primed the pump basket, turned on the pump and the pump primed itself just like when it was new, hardly any air bubbles in the basket and none coming out of any of the jets. I did the same thing with the Skimmer line getting the same good results. At this time only the Skimmer is connected so that I can vacuum the pool but I notice that when I connect the vacuum hose a goodly amount of air shows up in the pump basket with the pump running. After running the vacuum for some time the air finally starts showing in the jets as well. So there is still a problem but much less than before. Any suggeestions out there? Water too low over the skimmer intake, faulty vac hose or what else? Also,it has been a long while since I have done any PVC piping and I notice that there are many different types of PVC glue now offered on the store shelves. Is there any special type of glue that would be much better than the others to use in the pool plumbing? Thanks in advance for any help.
Ken
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Ken
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It sounds as if you've ID'd the main fault when you removed those old valves and tested both lines directly. So that's good. At some point I suspect you'll install new valves and be good there. As for the vacuuming, it's common to get air in the basket. No matter how good you prime that vacuum hose, or how new it is, it's never as good as the plumbing itself and air seems to get in. Sometimes, the suction is so great that the hose itself can collapse restricting water flow. When I vacuum, my pump basket water level drops down halfway. I just monitor things to ensure water is still flowing well and my vacuum suction is strong. For the glue, you can use the standard 2-part, or there is a blue 1-part PVC glue out there as well. So you have options. If you have room, you might consider installing the new valves with union fitting so that if you ever have to remove them again, you can simply unscrew them.