Quick Answer:
If your kitchen sink started to drain more slowly after you switched detergents, it’s likely residue from the new formula is clinging to the pipe walls or the disposal. Start by testing the drain before and after detergent use, flush the line with hot water, clean the strainer and garbage disposal, and remove the P‑trap to clear any buildup. If those steps don’t restore normal flow, call a plumber.
Why This Happens
Different detergents use different surfactants, thickeners and additives. Some formulas leave a thin, greasy or gummy film that can catch food particles and soap scum. Over time that film narrows the pipe and slows flow. If you’re already seeing slow performance, you may find the same pattern as other homeowners reporting Kitchen sink draining slowly after a change in cleaning products.
Step-by-Step What to Do
1. Test the drainage before and after detergent use
- Run the faucet at full flow for 30 seconds and note how quickly water leaves the basin.
- Do a controlled test after using the new detergent: wash a few items, rinse them as you normally would, then run the faucet again and compare times. This directly shows whether the detergent correlates with the slowdown.
2. Flush with hot water
- Boil a kettle and carefully pour hot (not boiling if your sink is porcelain) water down the drain in two or three stages. This helps dissolve greasy residues.
- Repeat the test to see if flow improves.
3. Clean the strainer and garbage disposal
- Remove the sink strainer or basket and clear any trapped debris.
- If you have a garbage disposal, run it with cold water and small ice cubes to dislodge soft buildup, then grind a lemon wedge or a small handful of baking soda and run water to rinse. Always disconnect power before sticking your hand in the disposal.
4. Use a safe mechanical method
- Try a plunger over the drain (seal the other basin if you have a double sink). Several firm plunges can dislodge residue.
- A drain snake (hand auger) can reach a few feet into the pipe to pull out trapped material. Go slowly and avoid forcing it if you meet strong resistance.
5. Clean or remove the P‑trap
- Place a bucket under the P‑trap, loosen the slip nuts, and remove the trap to clear accumulated gunk. Clean it with a brush and hot water, then reassemble. If you’re uncomfortable, this is a good point to stop and call a pro.
- After reassembly, run water and repeat the drainage test. If the pattern is odd — for example the sink gets faster as the water level drops — note that behavior; it can match cases of Kitchen sink drains slow then speeds up and helps a technician diagnose the issue.
What Not to Do
- Do not ignore detergent residue effects. If a new product causes slow drainage, stop using it and test whether the problem clears.
- Do not mix household chemicals (for example, bleach and ammonia) — mixing can create dangerous fumes.
- Avoid repeated pours of powerful chemical drain openers. They can damage pipes and harm septic systems. Use mechanical cleaning first or get professional help for stubborn clogs.
- Don’t keep forcing a snake or tools if you meet hard resistance; you may damage the pipe or push the clog deeper.
When to Call a Professional
- Water still drains slowly after you’ve cleaned the strainer, flushed with hot water, cleared the P‑trap and tested again.
- There is standing water that won’t move, multiple fixtures are slow, or you smell sewage.
- You’re not comfortable removing the P‑trap or working near the garbage disposal motor, or you suspect a deeper blockage in the main drain line.
Safety Notes
- Turn off power to the garbage disposal before working on or near it.
- Wear gloves and eye protection when removing traps or scraping buildup.
- Handle hot water carefully to avoid scalding; don’t pour boiling water into a cold porcelain sink.
- If you use any commercial cleaners, follow label instructions and ventilate the area. Never mix cleaners.
Common Homeowner Questions
- Why did switching detergents cause this? — Some detergents leave residues that trap grease and particles, narrowing the drain over time.
- Will vinegar and baking soda fix it? — They can help loosen mild buildup and are safe for many sinks, but they may not solve heavier or mechanical clogs.
- Can I keep using the new detergent if I clear the pipes? — Try a small test batch and flush the drain well after each use; if slow drainage returns, switch back to the previous product or a milder formula.