The answer to 'water heater foul smell' is that a foul odor coming from your water heater is often caused by a buildup of bacteria, which can produce a rotten egg or sulfur-like smell. This is a common issue that requires prompt attention to prevent further problems.
The most common causes of this problem are a lack of maintenance, sediment buildup, or issues with the anode rod. Sediment can trap bacteria and create an anaerobic environment, while a worn-out anode rod can allow more corrosion and bacterial growth. Addressing these issues through regular flushing and anode rod replacement can often resolve the problem.