If your kitchen sink won’t turn on, start with water supply valves, aerator clogs, and—on touch models—dead batteries or a tripped GFCI.
Nothing feels more disruptive than turning a handle or tapping a sensor and getting silence. The good news: most “no flow” issues come from a short list of culprits you can check in minutes. This guide walks you through quick diagnostics for standard and touch/sensor faucets, simple fixes, and when to call a pro.
When The Kitchen Tap Won’t Start Flowing
Start close to the faucet, then move upstream. You’ll rule out small blockages first, then look at supply, then household issues like frozen lines. Keep a towel, a small bowl, an adjustable wrench, and a pair of pliers nearby. If you have a touch or touchless model, grab fresh AA batteries.
Fast Diagnosis Roadmap
Work through these checks in order. Each step takes a minute or two and narrows the cause fast.
| Symptom | Likely Cause | Quick Test |
|---|---|---|
| No water on hot and cold | Closed under-sink valves or clogged aerator | Turn both stop valves fully open; remove and rinse aerator |
| Only hot or only cold is dead | Shutoff for one side closed or cartridge debris on that side | Open both stops; try hot/cold sides separately |
| Touch/touchless does nothing | Dead batteries, solenoid lockout, or GFCI trip | Swap batteries; reset GFCI; switch to manual bypass if supported |
| Weak dribble that stops | Mineral grit in aerator or internal screen | Unscrew tip; flush; test flow from hose before reinstall |
| Nothing at any faucet | Main shutoff closed or frozen service line | Check another sink; inspect main valve; assess temps |
Step-By-Step: Standard (Non-Sensor) Faucets
1) Confirm Under-Sink Stops Are Open
Look beneath the sink for two small valves—one for hot, one for cold. Turn each counterclockwise until it stops. Quarter-turn valves should be parallel to the pipe when open. Many “no water” calls end here.
2) Clean The Aerator
Grit and scale collect at the faucet tip. Wrap the spout with a cloth, grip the aerator with your fingers or pliers, and unscrew it. Rinse out debris, reassemble, and reinstall. If it’s packed with scale, soak parts in warm vinegar for 15–30 minutes, rinse, and reattach. Moen’s service library recommends routine aerator cleaning for low or no flow issues, and the steps are straightforward (Faucet Aerator Cleaning).
3) Check Pull-Down Hose Screens
On pull-down or pull-out models, a fine mesh screen sits between the hose and spray head. Unscrew the spray head, look for a small screen, rinse it, then briefly run water with the hose pointed into the sink. If the hose blasts with good pressure, the screen or spray head was the choke point.
4) Try Hot And Cold Separately
Turn the handle to full cold, then full hot. If one side flows and the other doesn’t, the closed stop valve or debris on the corresponding side is to blame. Some manufacturers note that low flow on only one temperature often means the cartridge needs service or replacement (Kitchen Faucet: Low Flow).
5) Inspect Supply Lines For Kinks
Look for sharp bends in the braided lines from the valves to the faucet. Straighten gentle kinks by hand. If a line is crushed or frayed, replace it before turning water back on.
6) Flush The Faucet Body
Mineral grit can lodge inside the faucet. Shut both stops. Disconnect the hot and cold lines at the faucet inlets, place ends in a bowl, and crack each stop slightly to flush clean water. Reconnect, open stops fully, and test. This clears construction debris and sediment without full disassembly.
Touch And Sensor Models: Power, Solenoid, And Bypass
When a touch or hands-free kitchen faucet won’t respond, power is the first suspect. Most systems run on AA batteries, and many give a red LED or slow response before quitting. Delta’s support pages outline battery specs and lifespan hints for common models (Touch2O battery info).
1) Swap The Batteries
Open the battery box under the sink and replace all cells with fresh alkalines in the correct orientation. Don’t mix old and new. After swapping, wait a few seconds and test the sensor or touch band. If flow returns, recycle the old batteries and note the date for next time.
2) Check The GFCI
Some smart faucets use a nearby outlet for an AC adapter. If that outlet is GFCI-protected, the solenoid may lose power when it trips. Press RESET on the GFCI faceplate and retest the faucet. A tripped GFCI often pairs with a recent splash under the sink or another appliance on the same circuit.
3) Inspect The Solenoid Connections
Follow the wires from the battery box or adapter to the solenoid valve. Confirm each connector is fully seated and dry. Tug gently to check for loose clips. If the solenoid clicks but no water flows, mineral grit may be jammed at its inlet screen. Shut water off at the stops, remove the hose, and rinse any grit out.
4) Use Manual Bypass (Model-Specific)
Many touch models can be run in manual mode while you sort power issues. For Delta kitchen units, support pages describe simple ways to bypass the solenoid so the handle controls flow until you fix the electronics (Touch to Manual; broader smart faucet help).
Household-Level Causes: If Multiple Fixtures Are Affected
If a second sink is also dry or barely dribbling, the issue isn’t just a single faucet. Check these wider sources:
Main Shutoff Moved
Remodels, appliance installs, or emergency shutoffs can leave the main valve partly closed. Locate the main, usually where the service line enters the home or near the water meter. Turn it fully open. If movement feels gritty or the stem leaks, stop and call a plumber.
Frozen Supply Lines
In a cold snap, lines near exterior walls can freeze. Typical signs are silence or a tiny trickle that fades. Keep the faucet open and warm the pipe area with gentle heat: a hair dryer, a heating pad, or a space heater in the room. Skip open flames. The American Red Cross offers clear safety steps for thawing (frozen pipes guidance).
Clogged Whole-House Filter Or Softener Bypass
If the home uses a cartridge filter, a clogged element can choke flow to all taps. Check the system gauge, replace the cartridge if needed, or switch to bypass to test. Restore normal setup after testing.
Deeper Fixes For Persistent No-Flow
If the simple checks don’t restore service, you may be facing internal wear, a failed cartridge, or heavy debris. These steps take longer but still work well for an experienced DIYer.
Disassemble And Inspect The Cartridge
Shut both stops and relieve pressure by flipping the handle to “on.” Pop the handle cap, remove the set screw, lift the handle, and access the retaining nut. Pull the cartridge straight up. Look for torn seals or grit. Rinse, re-grease O-rings with plumber’s grease, and reassemble. If the faucet still refuses to flow—or only one temperature works—install a new cartridge made for your exact model.
Flush Supply Lines Thoroughly
With the cartridge out, place a towel over the valve body and crack each stop briefly to blast clean water through the faucet body into the sink. This purge clears fine sand from new construction or main work on your street.
Replace Worn Spray Head
Mineral scale can clog fine passages inside a spray head. If cleaning only helps for a day or two, a replacement head often restores normal flow for years.
Touch & Sensor Troubleshooting Table
Use this quick chart to isolate electronic faucet issues. Always shut water at the stops before disconnecting hoses or solenoids.
| Part | What To Check | Likely Fix |
|---|---|---|
| Battery Pack | LED on base blinking red; recent slow response | Replace all cells; align polarity; retest |
| Solenoid | Clicks but no flow; debris at inlet screen | Remove hose; rinse screen; reinstall; flush |
| Sensor Window | Dirty lens; false triggers; no detection | Wipe lens dry; power cycle; re-aim |
| GFCI/Outlet | No power to adapter; test button popped | Press RESET; move plugs to dry location |
| Manual Bypass | Electronics unresponsive during cooking or cleanup | Use model-specific bypass to keep water on |
Why Aerators And Screens Block So Often
Anytime a utility flushes mains or a city repairs a break, fine grit moves through service lines. Aerators and internal screens are designed to catch that grit before it reaches the valve. Routine cleaning is simple and recommended by major manufacturers, and it can restore full flow in minutes. If you live with hard water, a monthly vinegar soak keeps parts clear.
Prevention: Keep Water Ready On Busy Days
Schedule Small Maintenance
- Rinse the aerator every few months.
- Change touch faucet batteries annually, or sooner if the LED blinks.
- Open and close under-sink stops twice a year to prevent seizing.
- Replace frayed or bulging supply lines on sight.
Winterize Vulnerable Runs
Insulate pipes in cabinets along exterior walls and keep those doors cracked during cold snaps. Let a thin stream run overnight during severe cold. If a line freezes, use safe heat and keep the faucet open—as the Red Cross notes, moving water helps thaw safely while pressure vents at the spout (frozen pipes guidance).
Mind Whole-House Filters
Mark your calendar for cartridge changes. A collapsed filter can choke every fixture and make troubleshooting confusing.
When To Call A Plumber
Pick up the phone if:
- Both stops are open, the aerator is clear, and there’s still no flow.
- The handle moves loosely or grinds, hinting at broken internal parts.
- You see leaks while testing, especially at the valve body or supply lines.
- Frozen lines don’t thaw with safe heat, or you suspect a burst section.
A pro can pressure-test, isolate a failed cartridge or solenoid, and clear debris deeper in the system with the right tools.
FAQ-Style Quick Wins (No Fluff)
Why Do I Get A Short Burst, Then Nothing?
The valve opens, pressure drops against a clog, then flow stops. Clean the aerator and any in-line screens; flush the faucet body.
Why Does Only Cold Work?
The hot stop under the sink might be closed or the cartridge’s hot passage is blocked. Open the stop and flush. If flow returns on cold only, service or replace the cartridge.
Can I Keep Water Running If The Touch Feature Fails?
Many models allow manual operation while you sort power. Delta details several ways to do this on kitchen units; follow the exact method for your model (Touch to Manual).
Wrap-Up: A Repeatable Plan
Start at the spout: aerator off and clean. Open both stops. Test hot and cold separately. On pull-down models, rinse the hose screen and try flow from the hose alone. For touch or hands-free, replace batteries, inspect connections, reset the GFCI, and use manual bypass if available. If the whole home is affected, check the main and consider frozen lines. With that sequence, most kitchens go from silent to flowing again in short order.