Pool School Freshman

[bigskinny18]

Just bought a great house with an awesome pool. Previous owner gave me a good run-down on how everything was installed and what he did to maintain. His first instruction was to get into Pool School and become pool knowledgeable (this is also my first forum post). We walked through a filter cleaning together and he told me the pump should run relatively slower once the filters have been cleaned and the pump back online, which makes sense. The filter pressure was about 8psi. He was showing me the speed in watts (about 350w) but I may have missed what the RPM were. Others I've talked too know their pump RPM speed rather than how many watts are being used.

It may have taken a cycle or two, but as is usually the case, things seemed to have changed and the pump is now running much higher than it did when we walked through it together. I also got an alert to service system soon an the pump showed that the filter was 100% blocked. I ran through a filter cleaning myself and put the unit back together, but the alert still showed on the pump. After reading the pump manual I realized this is because the pump is basing everything on pressure and the clean filter pressure was set to 10psi yet the filter pressure was operating around 20psi. Also, the pump manual said the system needed to go through a backwash cycle to clear the alert.

I'm still learning the pump control settings, but was able to switch to manual mode and the pump is now running with about 15psi on the filters. I know it's different for each pool based on piping layout, but I'm wondering what the average range of pump RPM speed, cycle times, number of turnovers in a day, filter pressure, etc,. The cartridge filters are 7years old so I'm wondering if it's time to start with a new set of cartridges before looking into other possible issues.

Appreciate anyone's support!

 

[pooldv]

Welcome to TFP!

Congrats on the new pool! The Intelliflo VF (variable flow) is different than the VS (variable speed). The VS is set using RPM and the VF is set using GPM (gallons per minute). So, if you set the VS to 1500 rpm it will always run at 1500 rpm and as the filter clogs up the water flow will be reduced. The VF is set to say 30gpm and it might run at 1500 rpm for a while but as the filter clogs it will increase RPM to maintain the 30gpm flow rate. This makes it more important to monitor your filter pressure and pump speed because you can unknowingly go from using 350 watts to using 2500 watts or more to keep up the same flow rate.

We recommend cleaning your filter when the pressure rises 20-25% above clean pressure. You need to check pressure periodically at a higher rpm/flow rate, like maybe 3000 rpm.

Now that VF pump 101 is covered. That is the biggest cartridge filter that Pentair makes and unless you have a LOT of trees and debris falling into your pool then you should only need to clean that filter twice a year, or maybe once. It it is clogging quickly then you more than likely have algae growing in the pool. Nothing clogs a filter faster than algae growing in a pool.

Low chlorine levels cause (allow) algae to grow in a pool. Chlorine level is set based on the CYA level and the [FC/CYA][/FC/CYA]. FC must always be kept above minimum to keep the pool sanitary and prevent algae.

You will need a great test kit to be able to effectively maintain your own pool. I use the TF-100 and I buy mine from TFTestkits.net.

Get the test kit, post some test results, do an Overnight Chlorine Loss Test to see if there is something growing in the pool. If there is then kill it with this process, SLAM Process

Start here in Pool School, ABCs of Pool Water Chemistry

 

[bigskinny18]

Definitely have something growing in the pool. Previous owner had several bottles of bleach out by the pool. I kept adding several bottles but the FC never increased. Then I read that the bottles should be kept out of the sunlight. By the time I figured out the bleach I was adding was compromised, I bought some new bottles and instantly the FC was up to 12ppm. Since the cartridge filters are about 7 years old I'm thinking they should be replaced prior to SLAMing the pool.

I have a TF-100 kit that the previous owner left me and have been checking levels almost every other day. CYA has been about 60 to 50, salt 3200, CA 320, TA 90, and pH was 7.6

 

[pooldv]

Check out some Pleatco replacement cartridges, they are cheaper, better, easier to clean all around better.