Correct Swimming Pool Filter Pressure
Lets take a look why a correct swimming pool filter pressure is a very important part in a proper pool operation.
Having a correct swimming pool filter pressure means that the pool water has its maximum flow though out the whole piping and filtrates as much gallons of water as it could be per hour. That also creates a good water flow trough out the whole pool, the water moves around the pool rapidly and does’t let any algae to grow up on the surface. So by having a good flow in the pool is critical to keep surface of a pool free of algae.
There are 3 types of pool filters on the market, which is Cartridge, Sand and D.E. (Diatomaceous Earth) Filters.
Since a cartridge pool filter is the most popular one in the private (single family house) pools, we’ll take a look at this one first.
This particular method is for any cartridge pool filter
OK so fist thing first, make sure all skimmers and pump basket free of any debris. Now you need to find out what is the minimum pressure in your filter to get an idea what is optimal pressure then. You would have to FIRST OF ALL shot off the pump and open your filter then take a filter cartridge out and close it with out a cartridge (so the filter remains empty inside). Now turn the pump on and look and the Filter Pressure Gage, this would be a minimum pressure measured by PSI.
The minimum pressure could be 0 psi or may be some where at 5 or 7 psi. its all depends on how many elbows or T-pipes or water falls you have in your piping. So write down this number and you are ready to turn off the pump and reinstall your cartridge back in the filter. Now we need to see your existing pressure with a cartridge installed.
Now subtract minimum pressure out of the existing one and you get a correct pressure from the cartridge. This pressure can vary from 7 psi to 30 psi (where 7 is optimal good and 30 is very bad) depending on the condition of your cartridge.
When a cartridge needs to be clean?
When a Cartridge exceed 15 psi of pressure over time that means it’s a time to take it out and clean it.
For Example: If the minimum pressure in the filter with out a cartridge is 5 psi and with a cartridge installed is 15 psi, that means the cartridge pressure it self is ONLY 10 psi, which means that your cartridge is in the good shape yet. Majority of people determine the cleaning time by just looking at the pressure Gage and not knowing that the piping it self has its own pressure as well. In this case the cartridge needs do be cleaned after at least exceeding 20 psi on the Gage.