Air bubbles under the lid

[jan verbeem]

@JamesW I have a no return valve on the output of the pump, so pressure will not go backwards I assume.

What I do notice is that when the filter cycle ends, I get a large air bubble in my chlorinator cell housing.

When I then start the pump again, I get quite a lot of air under the lid for a few seconds only.

I let the pump run for 20 seconds and switch off, air bubble in cell housing is gone.

Start the pump again, no air under the lid at start up

 

[JamesW]

Is the cell still generating when the pump is off?

If yes, the chlorine gas and hydrogen gas can explode.

Check the pump drain plugs to make sure that they're secure.

Check the pump lid O-ring. Make sure that it's clean and lubricated.

 

[jan verbeem]

Is the cell still generating when the pump is off?

If yes, the chlorine gas and hydrogen gas can explode.

Check the pump drain plugs to make sure that they're secure.

Check the pump lid O-ring. Make sure that it's clean and lubricated.

Pump is controlled by the chlorinator. Big air bubble in the cell comes from the return line.

Drains plugs dry as a desert.

Air bubbles visibly come out of the tube.

Not sure if you seen my last post, so I paste it here again.

When I then start the pump again, I get quite a lot of air under the lid for a few seconds only.

I let the pump run for 20 seconds and switch off, air bubble in cell housing is gone.

Start the pump again, no air under the lid at start up

 

[JamesW]

Maybe a picture or video would be helpful.

You might have a suction line air leak underground.

Underground suction leaks can be intermittent due to the fact that it's suction but maybe not enough to draw continuous air.

Sometimes the ground is saturated with water and the water covers the suction leak.

If you want to be thorough, you can pressure test the entire system.

You really should have a skimmer basket to keep large debris from clogging the plumbing.

 

[jan verbeem]

Maybe a picture or video would be helpful.

You might have a suction line air leak underground.

You really should have a skimmer basket to keep large debris from clogging the plumbing.

Filter pump is the one in the back.

I know I should use the hayward connection unions, but for some reason they were not delivered with the pumps, and to buy them separate they cost 25 US$ a piece here.

The connection union I use is mounted with RTV silicone and 100% doesn't leak.

 

[JamesW]

If you have a suction leak, I would suspect that it's at the threaded fitting going into the pump or the drain plugs or the lid O-ring.

Try getting close and turning the pump on and off a few times to see if that tells you anything.

Check to make sure that the pump basket is installed correctly.

Check under the pump for a seal leak.

 

[jan verbeem]

If you have a suction leak, I would suspect that it's at the threaded fitting going into the pump or the drain plugs or the lid O-ring.

Try getting close and turning the pump on and off a few times to see if that tells you anything.

I'm pretty sure the threaded fitting doesn't leak, but does the following give you any indication.

After filter cycle finish, strainer is full of water, no air space between water and lid.

I switch on the pump, it sucks a lot of air under the lid for may 3 - 4 seconds only.

I let the pump run for 20 seconds and switch it off again.

After that I can switch it on immediately or after 10 hours, the air suction as previously mentioned will not happen.

So after a filter cycle ends there must be a big air bubble at the suction side of the pump, and it is not water flowing back to the pool when the pump is switched off, because then it would also happen the next time I start the pump.

 

[JamesW]

If the SWG is off, do you get continuous bubbles out of the returns?

 

[jan verbeem]

If the SWG is off, do you get continuous bubbles out of the returns?

I get just 1 or 2 large bubbles out of the return into the cell housing right after the cycle ends.

No air bubbles thereafter.