I wanted an economical, on demand, method of providing taste free drinking water without filtering shower, toilet and sink water as well.
I bought this from Camping World for $57, it is an easy install also designed for winterizing. The water has no smell of chlorine and tastes just great.
Culligan RV-EZ-3 Under sink Water Filter Kit with Faucet - Culligan International RV-EZ-3 - Water Filtration - Camping World
Here are the items unpacked, note the small round object with the two spigots, this is the winterizing blank which allows removal of the filter cartridge so that antifreeze can be circulated. Also taped to the filter is a battery which is for the filter change warning light.
We have a rear kitchen arrangement so access to the rear of the sink is easy. Choose a location for your new drinking water faucet that is convenient and mark with a pencil where the 5/8ths hole for the threaded pipe must go then check carefully underneath to ensure that your location gives enough space for the large washer and nut and does not interfere with any pipes or electrical cables. Use a tape to measure and remeasure the location before you start drilling holes. Also ask the DW if she is happy with the location.
When you are 100% sure your location and pencil mark is correct drill a small 1/8th inch pilot hole, check underneath to make sure the hole is where you expected it to be. If all okay use a 5/8ths drill bit to make the hole larger. My largest drill bit was only 3/8ths so i used that and used a rat tailed file to enlarge the hole enough so that the new faucet threaded pipe would fit through.
Install the new faucet into the hole and from underneath install the large metal washer and nut to finger tight.
Turn off the city water supply and drain any water out of the cold side of the system by opening the cold water on your kitchen faucet. Have some absorbent material at the ready to mop up a few drips. Disconnect the cold water supply line from the cold water inlet pipe, this may be only finger tight, if not use an adjustable wrench or pliers depending on your fitting to loosen the fitting. The photo shows the cold water fitting disconnected and the new T fitting in position prior to fitting. Note: the new faucet is installed but not yet tightened to finger tight.
Here is the T installed, all fittings tightened finger tight then snugged up half a turn with a wrench. I applied Teflon tape to both the threaded faucet pipe and to the male threaded part of the T. The nut on the new faucet has been tightened in this photo.
Next we need to mount the filter cartridge holder, choosing the correct location is important, it must be accessible and the screws that hold it in place must be screwed into something solid. I chose the inside frame of the kitchen unit but used shorter screws than those supplied so that they would not protrude through the wood. You must have a total of 16 inches so that there is enough clearance to exchange cartridges.
Next install the tubes that carry the water, three of the fittings are simply push fit and one is a compression type. Cut the tube with a sharp knife make sure you have enough so that there are no tight turns or kinks. From the T to the left side of the cartridge holder (it is marked IN) these are both push fit. Then from the right side of the cartridge (marked out) this is a push fit, install the tube and then the other end is a compression fit to the new faucet, the enclosed instructions show clearly how this compression fitting works. Wet the ends of the tubes when it is a push fit. Use a cable tie to tidy up the tubes and keep them out of the way.
This photo shows the cartridge installed it simply pushes in and a 1/4 turn locks it and the water tubes in place.
Turn on the city water and check for leaks, then install the battery.
The unit comes with a battery operated warning light that flashes when the cartridge needs changing. Strangely there is no mention of this in the instructions, the instructions are excellent but this is missing, I think this is a recent modification and the instructions have not been updated.
The battery fits in this slot, it flashes red, turn on the water, let it run, turn off the water and the flashing red light stops and will probably not flash again until the cartridge need changing. the cartridge is good for 6 months or 500 gallons.