Kitchen water filters provide a convenient compromise between the cost of a whole-house filter system that installs on your primary water line and needs large filter parts, and also a mini-filter module that attaches to the existing faucet. A kitchen water filter installs under the countertop and supplies filtered water into a dedicated tap situated adjacent to the main sink faucet. The plan of under-counter water filters is simple and setup procedures are similar among all significant brands. Water is taken out of the supply line at a tee fitting beneath the sink, conveyed through the water filter, then piped to the filter tap. Most kitchen water filters use readily replaced cartridge filters.
Confirm the Valve
Before starting, you’ll want to switch off the cold water supply into the sink. There is an under sink valve for it. Make certain that you can flip it before you even look at doing the setup yourself. Several cutoff valves that haven’t been shut in years may be pasted in the open or partially-open place from mineral deposits and will want a plumber. Once the water is eliminated, you can follow the setup sequence in the company’s instructions.
To Drill or Not to Drill
Many sinks have predrilled holes for installing ancillary faucets and accessories such as soap dispensers. All these are often closed with plugs that, once eliminated, give a handy spot for installing the filtered tap component of an under-counter filter. The holes are standard size for a tap stem. If your existing sink does not come with predrilled holes, then you’ll need to drill. Stainless steel sinks are easily drilled with a standard metal drill bit. Most modern ceramic sinks may be drilled with a masonry drill bit. Granite or other stone sinks must only be drilled by a professional stone technician. Check the filter manufacturer’s instructions for the correct size hole. Pick the spot to the right or left of the existing main tap, then look under the sink to confirm that no plumbing or other obstructions exist. Use a punch to mark the spot first, then apply masking tape over the spot to keep the drill out of skittering and damaging the stainless steel or ceramic surface.
Tighter Is Not Always Better
After the tap is installed you’ll have to bring a tee fitting in which the cold water line connects to the sink tap to be able to divert water over to the filter. Another water line runs from the filter back to the filtered water tap. Both are easily-cut plastic tubing with compression fittings. Don’t overdo the tightening. Compression fittings on plastic tubing only need to be securely cozy, not torqued just like a lug nut. Leaks more frequently result from overtightening compared to undertightening.
Make It Easy on Yourself
When mounting the filter head under the countertop, then think before clearances. First of all, understand you’ll want to be getting down there frequently to alter the filter, so place it somewhere easily accessible. Also, consider that the screw-on filter pump needs ample clearance beneath it so as to unscrew the cylinder, lower it and then remove the replaceable filter cartridge. Put the filter head mounting bracket high enough at the under-counter area to permit easy removal of the cylinder.
Look for Leaks
After everything’s connected, place a fresh filter in the cylinder, and screw the cylinder into the filter head under the countertop. Make sure that the filtered water tap as well as the standard cold water tap are shut, then open the cold water shutoff valve. Together with the system under water pressure, observe all connections and confirm that nothing’s leaking.
Flush the Filter First
The first time you start the filtered water faucet after setup, allow the water run for many minutes to flush the filter. This procedure will be standard from now on each time you install a new filter cartridge if your machine uses common activated carbon filtration. The purpose would be to flush carbon “fines” — small gray or dark particles of carbon shed by a new filter — from the system. These are harmless but may be conspicuous in clear water.