pump starts with a lot of air in the system

[sdtfp]

For the past few days, when the system starts it's full of air. On startup, the returns look like when I flush out the system with air, so I think the filter dome thing is probably empty. I must I have an air leak causing the system to lose water into the pool over night.

Earlier this season when I opened I also had an air leak in the system but it wasn't this bad, the system would only have a little bit of air when it started up. But that had another side effect, it would discharge a ton of DE into the pool and it would be noticeably cloudy. This time, the pool is clear so it doesn't look like the earlier issue. Although the robot vacuum is picking up a little bit of DE, so maybe it is. I fixed that leak by cleaning the pump cover really well. The system was working really well after that.

So now I am wondering, do I have the same problem again, or is it different because of the different symptoms?

The only other thing I am concerned about is that the inline chlorinator broke, so I just bypassed it in the system with the hose it comes with. I would like to have a plug for the chlorinator holes in the plumbing so I can count that out as a problem. Anyone know where to buy that? I am not sure what to search for. It's a hayward chlorinator.

 

[Jimrahbe]

sd,

If your DE filter has an air vent valve, check to see that it is not leaking. I have seen them let air in when the pump is off, yet not let water out, when the pump is on. With the pump off, you can listen to it, or put your finger over the output and see if you can feel any suction as the filter drains down.

Thanks,

Jim R.

 

[sdtfp]

sd,

If your DE filter has an air vent valve, check to see that it is not leaking. I have seen them let air in when the pump is off, yet not let water out, when the pump is on. With the pump off, you can listen to it, or put your finger over the output and see if you can feel any suction as the filter drains down.

Thanks,

Jim R.

just to make sure, the filter air vent valve is the thing at the top that is connected to the pressure gauge right?

I do need a new one of those as I have a pretty old one.

 

[Jimrahbe]

just to make sure, the filter air vent valve is the thing at the top that is connected to the pressure gauge right?

sd,

Yes, it should have a handle that allows you to bleed the air out of the filter.. When the pump is running, you open that valve and let it stay open until water starts shooting out, then you close the valve. If this valve lets air leak in, when the pump is off, the filter will drain back into the pool.

Thanks,

Jim R.

 

[sdtfp]

sd,

Yes, it should have a handle that allows you to bleed the air out of the filter.. When the pump is running, you open that valve and let it stay open until water starts shooting out, then you close the valve. If this valve lets air leak in, when the pump is off, the filter will drain back into the pool.

Thanks,

Jim R.

Thanks for confirming. I checked on the filter air vent valve and it broke off the threaded part as I was screwing it in. It was a bit harder to remove than usual so I may have used to much force on that and then when I went to put it back it just snapped even though I wasn't doing it very hard at that point. So then I used my old valve and put it back and the issue is still there. I am waiting to get a replacement valve before I do anything further as I don't want to break the one I have now and not have a replacement on hand.

One thing I did notice is that when I removed the vent valve, DE went gushing back into the pool through the returns. That is not happening when the system is off, just air is getting into the system and water is going back to the system through the returns without a noticeable DE. I believe it's through the returns because the pump is full of water when I start it up. I am confused about why DE is not coming out of the returns when the issue happens over night. When a lot of air comes in through the vent valve it definitely pushes DE into the pool, but maybe if its a small amount of air over night then its not strong enough to push a lot of DE out? As mentioned, I do find a little DE on my pool robot, so maybe that is it.

I also have a very weird setup where I have a separation tank connected to the waste outlet of the multi valve and then the separation out line has a T where one side goes into the pool return and the other is plugged. See pictures. It is not an ideal setup but I haven't committed to removing the separation tank and fixing the plumbing and it has worked fine for the past few years. I mention it because when I turn of the pump, I can hear water coming out of the separation tank and I think I can hear it coming out of the filter as well. But the filter is plastic and thicker so its harder to tell if there is really the sound of water draining coming from it. I thought maybe it was the separation tank so I opened that up and cleaned/lubeds its oring. But the issue still persists.

Not sure what I will check next, but I'm wondering if its the multi valve. I recall seeing videos about replacing/lubing up the oring inside the multi valve but it seems too complicated and I didn't want to do it. Think you have to scrape the old one off and glue parts of the new one or something. I don't want to do all of that without being sure it's a multi valve issue. I also don't think I want to try that during the pool season as I don't know what I would do if it created more issues. I probably want to have a spare multi valve and some plumbing videos ready to go when I try something like that.

 

[sdtfp]

also can anyone tell me what I should buy to plug up the chlorinator holes in my plumbing. Attached is a pic with the small black lines that are used for the chlorinator.

 

[Jimrahbe]

sd,

A slow leak will not cause the DE to go back into the pool. As you found out, an large air leak will.

It may not be the air vent valve at all, it is just one of the things to check.

Thanks,

Jim R.

 

[sdtfp]

I think I found the leak. In the process of trying things I reseated the plug on the output of the separation tank. I must of made it worse because the next day I noticed it was leaking water out of there. So again I reseated that and the problem went away. The tricky part was that it was initially leaking air in but not water out, so no way to tell until I made it worse.