Q: When I turn on my air conditioner I smell a very bad odor, like sulfur or rotten eggs. The smell only lasts about 10 minutes when it’s first turned on. What causes this and how can I get rid of it?
A: Most likely, the filter and/or pan is matted with dust or rotten algae. Changing the filter might get rid of the smell. If a new filter doesn’t completely get rid of the problem, then it might be necessary to clean the coils and the pan that collects water. The job is similar to cleaning a bathtub or sink, so the same household chemicals can be used.