Eliminating a bad smell coming from a sink

There are times when a bad smell can come from a plumbing fixture.  In most homes, all plumbing is interconnected to the same sewage line, which means that if there is a bad smell coming from a sink, it might coming from a different drain.  Generally speaking, there are two main troubleshooting steps that need to be taken, before sending a plumber to the property.

Step 1: Fill a gallon (or larger) bucket with a mixture of 75% boiling water and 25% bleach.  Pour this down the drain and let it stay there for an hour.  After the mixture has sat for an hour, run the water again for 5 minutes.  Start with the fixture where the smell originates from.  If this doesn't resolve the issue, proceed to step 2.

Step 2: Mix equal parts vinegar and baking soda (1 gallon or larger).  When the mixture starts to fizz, pour it down the drain and let it sit for at least an hour. After it sits, pour boiling water down the sink and then let the water run for 5 minutes.

**If the property has more than one floor, be sure to use the same mixture in the upstairs bathroom sinks and shower drains.  
**If there are unused bathrooms or sinks, be sure to flush any unused toilets 2-3 times and let the water run in fixtures that are not normally used.