The Delta single-hole faucets are very easy to replace with a minimum level of skill and a few tools. Whether they are located in the kitchen or, the bath removal and installation is similar with minor variations.
The Delta single-hole faucets are designed to either mount in a single hole or, with the mounting plate provided mount over, and cover a three-hole sink. All of these faucets have integral supplies, and mount by the center hole where a screw extends through the single hole with the supplies, a washer and nut tighten the faucet in place. To replace a single handle faucet you will need: Silicone RTV, Adjustable Wrench, Channel Lock Pliers, 1/8” Allen Wrench, Phillips Screwdriver, and possibly a deep socket on older models, and plumbers putty on bathroom sinks if you are changing out the pop-up assembly (use Sta-Put Ultra if the sink is porous and can be stained by oil based putty). Some have integral supplies that extend all the way to the angle stop valves and others will require purchasing two faucet supplies separately to connect to the water supplies.
Kitchen Sink Faucets
The kitchen sink faucets can be removed by shutting off the angle stop valves then disconnecting the supplies. On sinks that have side sprays on older models require the use of a adjustable wrench to disconnect the side spray hose and on newer models have a quick connect that must be disconnected. After disconnecting remove the nut from the screw to allow the faucet to be removed from the sink mount. On older faucets a deep socket is required to remove the nut on newer ones there is a thumbscrew with a toggle on the top that flips back and forth depending on where you need it. Installing the new one involves sealing the o-ring with Silicone RTV if the mounting surface is uneven, putting on the washer and tightening the nut to secure it in place than connecting the supplies to the faucet and angle stop. Finally connecting the side spray quick-connect if you have one.
Pull Out Kitchen Sink Faucets
The pull out kitchen sink faucets have a larger screw coming through the hole and use a nut that is hand tightened then have jackscrews that tighten with a Phillips Screwdriver. The pull out hose has a weight that must be attached to the hose and the hose connects with a quick connect connector.
Bathroom Sink Faucets
The bathroom sink faucets connect and attach the same as the kitchen sink faucets except they also have a lift rod extending down through the faucet to operate the pop up assembly in some cases. The lift rod connects with a thumbscrew to the strap that operates the ball rod to make the pop-up stopper operate if used on your sink.