I am getting air in my sand filter-where should I look first

[Bob_Funk]

Good morning everyone,

This is my first pool, I have cleared it & have been enjoying it due to this forum for a month now.

My pump is not on a timer & I would like to install one, the problem is that my sand filter is getting air in it & when I shut the pump off, the air pressure is blowing all the water out of the return line, making the pump loose prime if I want to turn it back on.

I am not loosing any water, so I don't think I have a water leak, where should I start looking for the air leak?

Thanks

Bob

 

[JohnT]

The pump strainer basket lid being loose or needing a new O-ring or needing lubed is the first thing to check. Then the drain plugs in the pump as well as their O-rings. Then check that the pool water level is at or above the mark on the skimmer plate or about halfway, and that the skimmer weir isn't sticking.

 

[waste]

Hi Bob

John gave you the primary sources for air in the system Check those out before we start looking into the more exotic places pools leak

I'm thinking your filter system is above pool level and the water might be draining from the filter when you shut it off - the multi could be responsible for this... I'm thinking as I type but a check valve on the return might solve the problem, however, that would just be masking the air leak.

I'll just wait til you report back

 

[levieux7]

I had a crack in the pump pot lid that caused the same thing for me. When I replaced the lid, the air stopped entering the filter.

 

[Bob_Funk]

Hi & thanks for the ideas,

the skimmer lid o-ring is good & lubed up

the water level is good, & if a weir is the door that keeps stuff from floating out of the skimmer & back into the pool then it is also good

I will check the drain plugs in the pump tomorrow, I don't know where they are located, but I have the book for the pump(thank god, foreclosure home-the only thing left here from the previous owner was the pool equipment info) and will check that out

I don't think the lid has a crack but I will check when I turn the pump off tonight

I will report back tomorrow

thanks

Bob

 

[Bob_Funk]

Hi again,

I checked the drain plugs, both are good.

My pool has 1 skimmer, 1 drain in the deepest part & 1 return

The deep end drain meets at the skimmer & there is a valve to switch between skimmer only & skimmer & drain

If I have it on both skimmer & drain & cover the skimmer drain so the pump is just pulling from the deep end I get a ton of air in the pump basket

I was originally just running the pump with the water going only thru the skimmer until I figured out that to pull from the deep end drain I needed to turn the valve in the skimmer & that is when I started having problems with the air in the filter.

I could just run the skimmer return only but I am worried that I will not get good circulation in the deep end

any ideas?

Thanks

Bob

 

[duraleigh]

Sounds like that valve may be suspect. Inspect it closely for an air leak.

 

[JohnT]

The deep end drain meets at the skimmer & there is a valve to switch between skimmer only & skimmer & drain

If I have it on both skimmer & drain & cover the skimmer drain so the pump is just pulling from the deep end I get a ton of air in the pump basket

Can you post a picture Bob? It could be that the drain alone can't supply enough water to the pump.

 

[Bob_Funk]

Thanks for the replies,

I did a little more testing last night,

I backwashed the filter, pressure was up only 2psi, and I let the filter run 14hrs over night-skimmer & deep end, when I turned off the pump very slight back wash from the filter, the pump did not loose prime.

I think the problem may be too much sand in the filter, when I started working on this filter, I replaced the sand, I was still getting sand in the pool, so I had to take out all of the new sand.

I had all of the sand, old & new in a pile, I tried to fill the filter to the level it was, but it was just an estimation, my thought is if there is too much sand in the filter, stopping the water flow to the return instantly when I turn off the pump if the sand is dirty, when it is clean the water was still able to continue flowing to the return instead of blowing back out the skimmer line.

I have attached a pic of the skimmer/deep return valve at the end of the post

Am I off base here?

Should I take some sand out?

The pool is crystal clear.

thanks

Jordan

 

[Bob_Funk]

 

[duraleigh]

I'm not sure the sand level is related to losing prime. Most manufacturers have a mark or something in documentation to tell you how much sand. Sometimes you can find it on line. Short of that, most sand filters seem to do well about 2/3 full of sand and the top third empty.

Air in the system usually occurs on the suction side of the pump. Somewhere between your skimmer/main drain and your pump, air is getting in.

 

[Bob_Funk]

Air in the system usually occurs on the suction side of the pump. Somewhere between your skimmer/main drain and your pump, air is getting in.

You were right but I did not see it right in front of my face

I also have a 2 person in ground hot tub connected to the system, it was empty & the ball valves were closed but air was getting in.

As soon as I put enough water to cover the return the air leak was gone.

I have an OLD propane heater that I am going to remove along with the hot tub I am going to use those lines for solar

Bob