The article discusses the particular installation details for two-handle WaterSense bathroom faucets from AquaSource. The instructions should also work for other AquaSource faucets, as well as top-mounted bathroom faucets from other manufacturers. There may be slightly different instructions for other faucet models, however.
Tools and Materials You Will Need: New Faucet, Basin wrench, Channel-type pliers
How to Install an AquaSource Bathroom Faucet
First, shut off the water supply to the old faucet. Disconnect the water supply tubes from the tailpieces on the faucet, using a basin wrench or channel-type pliers.
Then, remove the faucet that is currently installed in the sink. A basin wrench is the best tool to use when removing the mounting nuts holding the faucet in place. This is a good time to clean the sink and remove any old putty or hard water build-up.
If you will be replacing the pop-up drain as well, now is the time when the drain trap and old pop-up should be removed so they are out of the way.
Next, install the new faucet body. From the top of the sink, put the faucet into place over the three faucet openings. To fasten the faucet into place, reach under the sink and install the lock nuts onto the two threaded tailpieces. Before completely tightening the lock nuts with a basin wrench, check to make sure that the faucet is centered and straight.
Connect the water supply tubes to the faucet, using channel-type pliers. It is always better to change the water supply tubes when installing a new faucet unless the existing ones are fairly new.