Why Does My Kitchen Sink Smell
- A rotting food smell from junk stuck in the garbage disposal or drain.
- Sewer smell from gas leaking in through the drain trap or vent.
Let’s look at each of these smells and what you can do get rid of it.
How to get rid of rotten food smell
Over time, gunk can build up in your kitchen sink drain and garbage disposal. Usually, this is from putting something down the drain that you shouldn’t have (such as grease, oil or fat.) To get rid of this smell, try these solutions:
Use a bio-enzyme drain cleaner These natural drain cleaners use enzymes that eat away at the food in your drain without harming your pipes. Here’s just one type. We recommend avoiding harsh chemical drain cleaners like Drano and Liquid-Plumbr.
Use vinegar and baking soda This is a drain cleaner you likely already have in your pantry. Sprinkle a half cup of baking soda down the drain. Then pour 1 cup of white vinegar into the drain. Let the solution foam up and sit in the drain for a little while. Then follow it up by pouring in a fair amount of hot (not boiling) water to clear the drain.
Run ice cubes through the disposal Ice cubes in the garbage disposal can help knock food particles off the blades. Follow up the ice cubes with one of the methods above.
Put lemon or orange slices in the disposal Running some nice-smelling citrus through the disposal can help your drain smell fresh and clean. However, if you don’t also do something to get rid of what’s causing the smell, it’ll just come back.
How to get rid of sewer gas smell Now, if you smell sewer gas, you have a different problem. This smell is leaking in from the sewer through the drain. This usually happens at one of two places: the sink trap or the plumbing vent.
The sink trap If you look under your kitchen sink you’ll see a sink trap. A typical sink trap. Public domain. Image source. The trap is so called because it “traps” a little water in the part shaped like a “u”. That water keeps sewer gas from making its way into your home. S
o if you smell sewer gas, check:
- That there is a trap. (Hey, we’ve seen it happen before.)
- If there’s a leak in the trap.
Also, if you haven’t used your sink in a while (because you were on vacation or something), the water in the trap can evaporate enough to let in some sewer gas. Luckily, the fix for that is easy: just run some water down the drain.
The drain vent You could have a perfectly functioning trap and still smell sewer gas. That’s because the pressure in the sewer fluctuates. High pressure can force its way through the water in the trap and low pressure can siphon out the water from the trap. That’s why homes have plumbing vents. The vents allow the changes in pressure to happen without gas ending up in your home. Vents are pipes that run vertically out of your home through the roof. Each drain in your home should be connected to a drain vent. Drain vent. Image by Martin2Reid. CC BY-SA 3.0 via Wikimedia Commons.
Problems with the vent can include:
- A blockage in the vent. (It’s not unheard of to find a bird’s nest in there.)
- A leaking vent. If the vent is near the sink, a leak could be letting sewer gas into your kitchen.
- No drain vent. Yup. It happens.