Commercial Faucet Dripping: Cartridge and Washer Troubleshooting
A faucet that drips after shutoff usually has a worn cartridge, stem washer, seat, seal, or debris preventing a seal. Identify the faucet type before disassembly.
Likely causes
Do not jump straight to the most expensive possibility. These are the common places to start:
- Worn cartridge
- Damaged stem washer
- Debris on sealing surface
- Worn o-ring
- Damaged valve seat
| Possible cause | How to check | Routine first move |
|---|---|---|
| Worn cartridge | Identify manufacturer and faucet style | Clean debris from sealing surfaces |
| Damaged stem washer | Shut off hot and cold stops | Replace the exact cartridge or stem kit |
| Debris on sealing surface | Open faucet to relieve pressure | Reassemble and test both shutoff and handle leakage |
| Worn o-ring | Remove handle and trim carefully | Clean debris from sealing surfaces |
| Damaged valve seat | Inspect cartridge, stem, and seals | Replace the exact cartridge or stem kit |
Tools and preparation
Bring these
- Flashlight
- Rags or towels
- Basic hand tools appropriate to the fixture
- Correct manufacturer repair parts when needed
Before touching anything
- Confirm the exact location and complaint.
- Photograph labels, settings, fault codes, and the original condition.
- Determine whether the failure affects one item or several nearby items.
- Know how to safely isolate the system if the task requires it.
Step-by-step checks
Identify manufacturer and faucet style
Work through this check deliberately and record what you find before moving to the next one.
Shut off hot and cold stops
Work through this check deliberately and record what you find before moving to the next one.
Open faucet to relieve pressure
Work through this check deliberately and record what you find before moving to the next one.
Remove handle and trim carefully
Work through this check deliberately and record what you find before moving to the next one.
Inspect cartridge, stem, and seals
Work through this check deliberately and record what you find before moving to the next one.
Routine fixes that make sense here
- Clean debris from sealing surfaces
- Replace the exact cartridge or stem kit
- Reassemble and test both shutoff and handle leakage
Common mistakes
- Replacing parts before proving the failure.
- Changing several settings or components at once.
- Failing to photograph the original condition.
- Ignoring whether nearby equipment has the same symptom.
- Crossing into electrical, refrigerant, life-safety, structural, or plumbing work beyond training.
When to stop and hand it off
- Supply stops do not hold
- Faucet body is cracked
- Cartridge is seized badly enough to risk breaking the body
Frequently asked questions
What should I check first?
Start by deciding whether the problem is local to one fixture or piece of equipment. Then begin with the simplest safe observation: identify manufacturer and faucet style.
What is the most common mistake?
Replacing parts before proving the failure. BuildingWrench recommends documenting the symptom, changing one thing at a time, and testing after each change.
When should maintenance stop?
Stop when the repair crosses your training or site-safety boundary. In this case, one clear handoff point is: supply stops do not hold.
What should I document?
Record the exact location, model or asset tag, what the equipment was doing, what you checked, what you changed, and whether the fix held through repeated testing.
Related BuildingWrench guides
BuildingWrench provides general educational information for commercial-facility maintenance. Manufacturer instructions, applicable codes, site procedures, and required trade qualifications always take priority.