I have inspected a rural property that the water has a strong sulpher odour. The property has a water softner. The question is should a water softner help eliminate the taste and smell of sulpher in water .
Water softener could be part of the problem among others such as the anode rod in the water heater or the well water in general.
You can figure out which by process of elimination pretty easy.
Hope this link helps…http://www.mrwa.com/watersmellrotteneggs.htm
Was this from both hot and cold water? Was the home vacant, if so, how long? Was the home on a private well? Answers to these questions will help with a possible diagnosis.
It could be a hot water heater that is not often used. They will smell like this