Hi all,

Learning quite a bit from these boards, but couldn't find anything that could put my mind at ease regarding my pool filter. I have an IG pool with Pentair SMBW 4000 DE filter and the top lid is expanding when the pool pump is turned on. The PSI reading on the filter is currently 24 with no DE on the elements. The filter is also leaking. I am concerned with the expansion and whether something can happen with the top lid that could cause some property damage or harm to someone.

Prior to today the PSI was 30 and I was able to get it down to 24 by rerouting outflow away from the roof solar heater and directly to the heater and then pool. Cleaning the elements did not lower the PSI and installing a new O-ring did not stop the leaks.

I have had this setup with a 30 PSI all summer without an issue. I don't understand why leaks are now visible and the lid is expanding.

Does anyone have any thoughts as to 1) whether the lid expansion is a risk 2) whether the expansion could be causingthe leaks 3) have any suggestions on how to resolve

I appreciate any help that can be provided.