Replacing an old faucet with a touchless sensor faucet is a straightforward job. The plumbing side is the same as any faucet swap — the only extra step is connecting the sensor control box and battery pack under the sink. This guide walks through everything: the tools you need, how to handle a 3-hole sink, the installation steps, and what to do if something doesn't work afterward.
Before You Start: What to Check
How many holes does your sink have?
Most sensor faucets are single-hole units. If your sink has three holes (one center hole for the faucet and two side holes for separate hot/cold handles), you need a faucet that includes a deck plate — a cover that sits over all three holes so the single-hole faucet fits without leaving gaps. Several Cascada sensor faucets, including the AquaSense Elite and AquaIntelligente, include a deck plate for exactly this reason.
Do you have an outlet under the sink?
Some sensor faucets can run on an AC adapter (110–240V) plugged into a standard outlet under the sink. Others run on AA batteries only. If you have an outlet nearby, you have more options. If not, a battery-only model like the AutoFlow Pro is the simpler choice. Battery models on this list average about 2 years of battery life.
Tools and Materials You'll Need
- Adjustable wrench
- Basin wrench (helpful for tight spaces under the sink)
- Plumber's tape (PTFE/Teflon tape)
- Bucket or towel to catch water
- Screwdriver
- Flashlight
- AA batteries or AC adapter (check your faucet model)
- The touchless sensor faucet kit (hardware included)
Step-by-Step Installation
Step 1: Turn off the water supply
Find the shutoff valves under the sink — one for hot, one for cold. Turn them clockwise until they stop. Open the faucet to release any remaining water pressure, and put a bucket or towel underneath to catch drips.
Step 2: Remove the old faucet
Disconnect the supply lines from the shutoff valves using an adjustable wrench. Reach up under the sink with the basin wrench and loosen the mounting nuts holding the faucet in place. Lift the old faucet out and clean the sink surface — any mineral buildup or old sealant should come off before the new unit goes in.
Step 3: Fit the deck plate (3-hole sinks only)
If your sink has three holes, place the deck plate over them first. It should cover all three openings and sit flat on the sink surface. The faucet mounts through the center hole of the deck plate. Some models include a gasket to seal the plate to the counter — fit this underneath before pressing the plate down.
Step 4: Install the new faucet
Drop the faucet through the sink hole (or center hole of the deck plate). From underneath, thread on the mounting nut and tighten until the faucet is secure and doesn't rotate. Don't overtighten — hand-tight plus a quarter turn with a wrench is usually enough on most sinks.
Connect the supply lines to the shutoff valves. Wrap the threads with plumber's tape before connecting for a better seal. Hand-tighten first, then snug with a wrench — no need to crank hard.
Step 5: Connect the temperature control
Most Cascada sensor faucets have a mixing valve that mounts under the sink. This is where you set your preferred water temperature — the sensor controls on/off, and the mixing valve controls how hot or cold the water comes out. Connect the hot and cold supply lines to the valve's inlets and the outlet to the faucet. The included hardware and instructions will show the exact connections for your model.
Step 6: Connect the power
- Battery models: Insert the AA batteries into the control box. Most models take 4 AA batteries.
- AC adapter models: Plug the adapter into the outlet under the sink and connect it to the control box.
Tuck the control box into a stable position under the sink where it won't get knocked around or sit in any water that drips.
Step 7: Turn the water back on and test
Slowly open the shutoff valves. Check all connections for drips — supply lines, the mixing valve, and anywhere tape was used. Hold your hands under the spout and the sensor should activate within about half a second. Pull your hands away and the water should stop.
If the temperature is off, adjust the mixing valve under the sink until it feels right. You won't need to touch it again unless someone wants to change the temperature.
Troubleshooting Common Problems
| Problem | Likely cause | Fix |
|---|---|---|
| Sensor doesn't activate | Batteries not seated / no power | Check batteries or AC connection; reseat if needed |
| Sensor fires when nobody's there | Object too close to sensor, or bright light hitting it | Move objects away from the spout; reduce direct light on sensor |
| Water drips from connections | Loose fitting or missing tape | Turn off supply, add plumber's tape, retighten |
| Low water pressure | Aerator blocked | Unscrew the aerator tip, rinse it clean, reattach |
| Sensor works but water is wrong temperature | Mixing valve not set | Adjust the under-sink mixing valve knob |
| Faucet shuts off after 60 seconds | Normal auto shut-off feature | No fix needed — this is how it works to save water |
If the sensor still isn't responding after these checks, see our sensor faucet troubleshooting guide for a full walkthrough.
Ongoing Maintenance
- Wipe the sensor window every few weeks. Soap scum and hard water film are the most common reason detection gets sluggish — it's not a broken sensor, it just needs a wipe.
- Check batteries when the low-battery indicator comes on. Most models give you a warning light before the batteries are fully dead. Battery life on these faucets averages about 2 years under normal use.
- Clean the aerator once or twice a year if you have hard water. Unscrew the tip, soak it in vinegar for 20 minutes, rinse, and reattach.
- Use mild cleaners on the finish. Avoid abrasive products or anything acidic — they'll dull or damage the chrome over time.
Installing Multiple Faucets?
If you're fitting several units for an office, hotel, or commercial restroom, the process is the same — just repeated. The main things to sort out in advance: whether the sinks have outlets nearby (which affects whether you go battery or AC), how many holes each sink has (so you have the right deck plates), and whether you want to match finishes across all sinks. Browse the full sensor faucets collection or call us at 800-766-7428 to talk through a project order.
Frequently Asked Questions
Do I need a plumber to install a touchless sensor faucet?
Not necessarily. If you're comfortable doing a standard faucet swap, a sensor faucet is the same process with one extra step — connecting the control box. If you're unsure about the plumbing or have a complicated setup under the sink, a plumber can do it quickly.
What is a deck plate and do I need one?
A deck plate is a flat cover that goes over the extra holes in a 3-hole sink so a single-hole faucet fits cleanly. If your sink has one center hole, you don't need one. If it has three holes, check that your faucet comes with one — several Cascada sensor faucets include it in the box.
Can I install a sensor faucet without an outlet under the sink?
Yes. Battery-operated models like the AutoFlow Pro run entirely on AA batteries with no wiring needed. Battery life averages about 2 years.
How do I set the water temperature on a sensor faucet?
Temperature is controlled by the mixing valve under the sink, not the faucet itself. You adjust it once during installation and the sensor handles the on/off from then on.
Ready to Upgrade?
See all available models in the sensor faucets collection. Not sure which one fits your sink? The touchless faucet comparison guide covers all five side by side.