Most newer refrigerators have a small plumbing line that feeds the ice maker and cold water dispenser. To keep that water and ice pure, there is a replaceable water filter that should be changed regularly. The frequency with which you change that filter will depend on the type of water you have in your area. Most manufacturers recommend changing the filters every six months, but some people will need to change it more often, while those lucky enough to live in regions with pristine water may find that once a year is sufficient.
Changing a refrigerator water filter is a quick and easy job. The best part about most of the refrigerator water filters used today is that once you unscrew the filter, it shuts off the water supply automatically—you don't need to worry about finding a shutoff valve to close.
Unless you know the brand and the precise model of your refrigerator, it is often easier to just take the filter to the local hardware or home improvement store. By ordering filters online from places like Amazon, Lowes, or Home Depot, you can usually get filters in two or three-packs to save money.
Twist-on refrigerator water filters usually may be located in the front of the refrigerator (usually in the bottom grille), the back, or the inside the refrigerator compartment. To change a twist-on water filter, simply turn the filter 1/4 turn counterclockwise, and then pull the filter straight out of the housing. The cover for this type of filter comes right off and can be used on the new filter. To reinstall, put the knob or cover on the new filter, push the filter straight into the housing and turn it 1/4 turn clockwise to lock it into position.
Make sure to dispense and throw away a gallon or two of water or discard at least the first batch or two of ice to remove the carbon residue left behind by a new filter.
Locate push-in refrigerator water filters in the bottom grille in the front of the refrigerator, inside the refrigerator in one of the drawers, or in the top of the compartment towards the back. To change a push-in filter, simply push the button to release the filter and then pull the filter out. Take the cap off of the old filter and push it onto the new filter. Then push the new filter all the way in until it locks into position. If there is no button, push on the filter to release the spring latch holding it.
As with all carbon-based filters, you should run and discard a gallon or two of water to remove the carbon residue from the water. If you only have an ice maker in the refrigerator, then you will have to throw away the first few batches of ice.