I am not sure why this is occuring and would like advise/feedback. It seems that when my cartridge filters get dirty air bubles start occuring under the lid of my pump basket. After a few days they create a large bubble that results in my SWG shutting off due to a low flow condition. If i clean the filters the problem goes away and everything runs fine. What could be the cause of this happening?
Air in pump Basket
- Thread starter George Whitzel
- Start date
George,
With that size filter you should not have to clean it but twice a year maybe less.. The fact that it gets dirty every few days tells me that you most likely have an algae bloom whether you can see it or not.
The first thing you should do is run an Overnight Chlorine Loss Test (OCLT)... here is how... Overnight Chlorine Loss Test Please follow the directions to the letter...
My guess is that you will fail the OCLT.. If you do, than you will need to do a SLAM SLAM Process
Thanks for posting,
Jim R.
With that size filter you should not have to clean it but twice a year maybe less.. The fact that it gets dirty every few days tells me that you most likely have an algae bloom whether you can see it or not.
The first thing you should do is run an Overnight Chlorine Loss Test (OCLT)... here is how... Overnight Chlorine Loss Test Please follow the directions to the letter...
My guess is that you will fail the OCLT.. If you do, than you will need to do a SLAM SLAM Process
Thanks for posting,
Jim R.
Another thought... What speed are you running your pump? If very slow, like 1000 RPM or so, then having a few bubbles under the pump lid is normal.. If you are running your pump speed so that the SWCG flow switch "just" closes, then it would not take much of a dirty filter to cause the flow switch to not close... My flow switch closes at about 1100 RPM, so I run my pump at 1200 RPM just to make sure the switch stays closed..
I ran the OCLT with OK results (FC 26 and CC off less than 0.5). The pool looks clear and can actually see the heads on a quarter someone dropped in pool when swimming on Saturday. I been running the pump at 1200 RPM except for when I am running my pool sweep where I increase it to 1800. This is a brand new SWG and I am not familiar with its characteristics yet. I cleaned filter cartridges this AM and very little came off them unlike before. Do not understand how dirty filter would result in air bubles under pump lid.
George,
My comment about dirty cartridges had more to do with the Flow Switch in your SWCG rather than bubble under the pump lid. As an example.. If your flow switch comes on at 1200 rpm, and you run your pump at 1200 rpm, with a clean filter the Flow switch will be closed. But as your filter gets dirty, the flow will decrease a little and can turn the flow switch off...
Bubbles under the pump lid at 1200 RPM is quite normal... What is not normal is for those bubble to get bigger and bigger until there is not enough water in the pump to work.
Bubble under the pump lid, will not shut your SWCG off...
Thanks,
Jim R.
My comment about dirty cartridges had more to do with the Flow Switch in your SWCG rather than bubble under the pump lid. As an example.. If your flow switch comes on at 1200 rpm, and you run your pump at 1200 rpm, with a clean filter the Flow switch will be closed. But as your filter gets dirty, the flow will decrease a little and can turn the flow switch off...
Bubbles under the pump lid at 1200 RPM is quite normal... What is not normal is for those bubble to get bigger and bigger until there is not enough water in the pump to work.
Bubble under the pump lid, will not shut your SWCG off...
Thanks,
Jim R.
As the filter becomes dirty the flow rate decreases.
Any air that enters the pump basket then has a much harder time to be pushed out through the pump due to the lower flow rate. So it effectively just collects and sits in the upper section of the pump basket chamber.
When you increase the flow rate back to a higher level the air can be forced out of the upper basket/lid area much easier.
Thanks for your replies as now I understand the cause and effect. I did an experiment this evening and with clean filters I can reduce my pump speed down to 1000 RPM and the SWG continues to operate and produce chlorine. I turned it back up to 1200 which is my regular run speed. So I guess the filters are doing their job and removing the debris.