Quick Answer:
Start by cycling the valve several times after reopening seasonal valves, then flush the line to clear any loose debris. If the drip gets worse, inspect the valve for mineral debris and consider replacing the cartridge. If you’re unsure or water is leaking into walls or ceilings, call a plumber.
Why This Happens
During winter, seals and cartridges can become stiff from cold and low use. When you open the water again, sudden pressure and flow can dislodge mineral deposits or grit that settled while the line was idle. Stiff seals may not reseat immediately, and small particles can lodge in the valve, stopping it from closing fully. Changes in house pressure after opening seasonal taps can also reveal or worsen leaks; for a different pressure-related drip check Shower drips when house pressure high.
Step-by-Step What to Do
1) Prepare and safety shutoff
- Turn off the water supply to the shower or the whole house if needed.
- Open a nearby faucet to relieve pressure before you work on the valve.
- Have towels and a small bucket handy to catch water when you remove trim or the cartridge.
2) Cycle the valve
- After reopening seasonal valves, cycle the valve several times by turning it on and off slowly for several cycles. This helps soften seals and move any loose debris out of the immediate sealing surface.
- Do this with the shower head removed (point tubing into a bucket) so you can see and direct the flushed water.
3) Flush the line
- With the shower head off, run the water at full on for 1–2 minutes to flush any sediment from the line. If you can, remove the cartridge briefly and flush directly from the supply ports to clear trapped material.
- Collect the water in a bucket to check for grit, sand, or small flakes of mineral scale. Presence of debris indicates the valve area may need a clean or cartridge replacement.
4) Inspect for mineral debris and cartridge wear
- Look at the cartridge and valve body for pitting, mineral deposits, or broken seals. Debris can sit in the valve bore and prevent a good seal.
- If debris is visible, gently clean the bore with a soft brush or cloth. Do not use wire tools that can score the surfaces.
- If the drip worsened after reopening and flushing, it often means the cartridge or seals are damaged or deeply clogged—consider replacing the cartridge.
5) Replace the cartridge if needed and test
- Install a correct replacement cartridge recommended for your valve. Reinstall trim and slowly restore water pressure, checking for leaks.
- Test by cycling the valve several times and watching for any slow drip. If the problem persists after a new cartridge, the valve body or plumbing may need professional attention — you may also find related issues in cases of continued dripping, see Dripping after replacing cartridge.
What Not to Do
- Don’t pour chemicals into the valve to “clean” it — these can damage seals and finishes and can be unsafe.
- Don’t rely on aggressive scraping or wire tools inside the valve bore; they can score surfaces and cause leaks.
- Don’t substitute incorrect or cheap replacement parts; use the right cartridge and seals for your valve model.
- If the valve sticks or leaking continues after simple measures, don’t keep forcing it — calling a plumber is appropriate.
When to Call a Professional
- There is active leaking into walls, ceilings, or cabinetry.
- You find extensive corrosion, a damaged valve body, or the cartridge is seized and won’t come out.
- The drip continues after cycling, flushing, and replacing the cartridge, or you’re not comfortable disassembling the valve.
Safety Notes
- Shut off and depressurize the water supply before removing trim or cartridge parts.
- Wear gloves and eye protection when working with tools and cleaning debris.
- Avoid chemical cleaners inside valves. If you must use any cleaner for visible scale, follow product instructions and manufacturer advice for your valve parts.
Common Homeowner Questions
- Q: Could seals have dried out over winter?
A: Yes. Cycling the valve often re-softens seals, but they may still need replacement if cracked or collapsed. - Q: Will flushing fix the drip?
A: Flushing can remove loosened debris and sometimes stop a drip; if the drip worsens or persists, inspect the cartridge and replace if necessary. - Q: How long before I should replace the cartridge?
A: If cycling and flushing don’t stop the drip or you see damage or scale on the cartridge, replace it promptly to prevent further leaks.
For more related articles, see the Dripping Showerhead After Shutoff hub.