We have a Jamboree 31M also. The filter to the drinking water faucet at the kitchen sink is the only filter other than the screen at the water connection. We remove the drinking water filter when we winterize, use pink RV Antifreeze and run it through all faucets, the stool, the outdoor shower and by pass the water heater. When dewinterizing, we use a cup of bleach in the fresh water tank, leaving it overnight and then flushing the water system and filling with fresh water. Your manual gives more detailed directions.