Install a Whole House or Under Sink Water Filter

What You'll Need
• Pipe cutter• Pipe wrenches• Plumber’s tape

All it takes to provide a healthier supply of water is the simple installation of a whole house water filter or under sink water filter. Drinking water that does not contain impurities is part of a healthy way of life. These water filters remove sediments from your water supply. Not only will this provide purer water for you to drink, but it may help extend the life of your appliances and plumbing system.

Consider a water filter with a built-in bypass for filter replacement. This allows you to replace the filters without having to turn the water off.

Instructions for Installing a Whole House Water Filter

Step 1 – Shut off the Water

Once you have purchased your whole house water filter and assembled the necessary tools, the first step is to shut off the water supply at the main supply line and drain the cold water from the plumbing system.

Step 2 – Pick the Filter Location

Select the area or section of the main line where you will install your whole house water filter. The location should be right after the water meter, or the bladder tank if you are on a well. This will filter the entire house. If it’s located just before the water heater, only the water to the heater will be filtered.

Keep in mind that you will need to change the filters, so place it in an area that will allow you to have easy access to the area where the filters are located.

Step 3 – Cut the Waterline

Use the template that came with the whole house water filter to cut the water line. Before you make the actual cutting, place a bucket underneath the area to catch any remaining water. Double check that you have cut the pipe to allow sufficient room for the filter system.

TIP:Our plumbing consultant Mark Vander Sande adds, “If the piping is galvanized pipe, you cannot simply cut it. It needs to be removed from joint to joint or fitting to fitting. Replace with new pipe nipples that will make up to the new filter.”

Step 4 – Install the Adapter Couplings and Compression Fittings

Install the adapter couplings onto the filter. You should have one for both the inlet and the outlet side of the filter system. Make sure that the water will flow into the inlet side of the filter system. Install the compression fittings supplied with your filter system to the water lines. Be sure that you attach these fittings securely to the adapter couplings for the filter.

Step 5 – Secure the Filter to the Wall and Turn On the Water

Using the wall mount provided with your filter system, attach it to the wall securely. Turn the water supply on again. Check the filter system and its fittings for any signs of leaks. Adjust the fittings if necessary.

Installing an Under the Sink Water Filter

Step 1 – Shut Off the Cold Water

Find the shut off valve for the cold water that leads to the sink and turn it off. Drain any water from the cold water tailpiece by disconnecting it from the supply line and draining it into a bucket.

Step 2 – Attach the Water Lines to the Filter

Install the adapters that came with your filter system onto the inlet and outlet areas of the filter system. Take the supply line and attach it to the inlet area of the filter system. Using the coupling/tubing provided with your filter system, attach the outlet valve of the filter system to the cold water tailpiece.

Step 3 – Mount the Filter under the Sink

Using the mounting hardware provided with your filter system, attach the filter system securely to the back of your sink cabinet. Turn the water supply on again. Check the filter system and its fittings for any signs of leaks. Adjust the fittings if necessary.

Mark Vander Sande, professional plumber, contributed to this article.

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