Most filters are on the inside of the fridge side with two lines running down the back and out the bottom, then over to the gate valve where there are 5 connections. The first sticks out of the back for you to hook your house water line to. The second is right behind the first it goes to the filter since the water and ice are filtered. The third is in the back of the unit where the water comes from the filter which is then distributed to one of the two in the middle for water or ice.
What Filters Do
The filter in your refrigerator is made to keep chemical contaminants and trace mineral deposits out of your water – things like chlorine, radon, benzene and anything else that might discolor or add a strange odor to your drinking water. The majority of fridge water filters do this by running water through activated carbon, which essentially leeches the contaminants out through a process called adsorption. Essentially, the atoms of the contaminants bond with and get "stuck" to the carbon in the filter. Bypassing the filter in your fridge may result in odd-smelling or less-than-clear water as a result. However, because the size and make of fridge water filters mean that they are unlikely to effectively filter out contaminants like lead, arsenic and other heavy metals – all far more harmful than trace amounts of chlorine – some consider them unnecessary.
In most cases, bypassing the water filter in your refrigerator is easy. The first step is to locate your fridge's filter. Generally, this will either be found inside the refrigerator door or behind the grille at the bottom of the refrigerator. If the filter is in the base grille, you can remove it by turning the round filter cover counterclockwise until the handle is vertical to the floor, and then pulling it out. If the filter is inside the fridge itself, push the release button beside it to release and remove the cartridge. Use a cup to test the water dispenser for a few moments. If it dispenses and continues to do so, your fridge has a built-in bypass and you're done. If it does not dispense, you will need a bypass plug. Replace the filter you removed for now.
If you require a bypass plug, you'll need to locate the specific make and model of your refrigerator. If you don't have the owner's manual handy, often this information can be found on the outside of the fridge or just inside the freezer door. Once you have it, purchase a bypass plug compatible with your fridge model, which can often be found via a quick online search. The plug will often look similar to your refrigerator's water filter. With the bypass plug in hand, simply remove your fridge's water filter and replace it with the plug, either by slotting it into the same port inside the fridge or by securing it to the same valve behind the base grille. Test your water dispenser for leaks and you'll be set!