Pool and Spa
Questions about Pool Repair? Ask an Expert Online.
All pool filters build up a vacuum seal when they have been running. Make sure that when you are trying to open the filter that you open the air relief valve located on top of the filter by the pressure gauge. You can also get a flat head screw driver and pry the lid up just a little with the screwdriver where the top and bottom meets as to break the air seal in filter this should release the lid.