What is a normal operating pressure for a jacuzzi sand filter for an above ground pool?"
when the pressure is high on filter mode it usually means that a backwash is required.
Let me say first backwashing is a process for simply ridding the filter of dirt, once you backwash the pressure and cleanness of the filter will begin to collect and store more dirt from the pool, Look at the gauge at the filter remember the pressure or write it down as the pressure goes up the flow of water going back to the pool will go down to the point that very little water will go back into the pool. When the pressure is low the water flow from the filter will be high meaning that the filter is not clogged or dirty.
Usually the pressure gauge on your pool equipment indicates how much pressure there is before the filter. as the pressure goes up it indicates that the filter is getting blocked and needs a backwash or cleaning. while the pressure is low the filter does not need cleaning.
because the leak releases pressure?
A pool with a sand filter or for that mater any filter is set up to push water through the fitter to be filtered. when the filter is clean the gauge in front of the filter Will have a low pressure reading. As the filter gets loaded with more of the dust and dirt that comes from the pools water it becomes harder for the water to pass through the filter and the pressure on the gauge goes up when the pressure get high on the gauge it is time to backwash the sand filter or to clean the cartridge filter. When the pressure on the gauge is high the suction from the pool is low. When the suction from the pool is low even when the pressure on the gauge is low there may be a problem with the pump, or a blockage between the pump and the pool, To increase the amount of pressure on a clean filter the only thing that can be done is to enlarge the pump.
The cleaning schedules varies from filter to filter, but a general guideline on any swimming pool filter is to take a reading when the filter is clean, then clean the pool filter when the pressure rises about 10 psi.
Backwash the filter when the pressure increases 10 psi above the pressure when it was clean
Clean the Filter!
Clean the filter, enlarge the filter, enlarge the pipes coming from and or to the filter, enlarge the pool pump, If you have a cartrige filter put another one in paralel next to it.
I think when it happens when the pool starts to turn green