It’s not worth fixing a 20-year-old dishwasher or any 20-year-old appliance. Twenty years is beyond the useful life span of nearly every major household appliance. Once the appliance nears the end of its useful life span, repairs will become more frequent. A replacement often becomes more cost-effective at that point.

The frequency for cleaning your dishwasher filter depends on your usage habits. If you run the dishwasher daily and don't scrape or rinse dishes before loading, you should clean the filter about once a month. For those who use it only once or twice a week and rinse items beforehand, cleaning it every three to six months may be sufficient. A clear sign that your filter needs cleaning is a musty smell, even after a wash cycle. Regularly cleaning the filter is important to prevent food buildup and clogging over time. It can be helpful to add this maintenance task to your calendar to stay on schedule.

Yes, you can use vinegar to unclog a dishwasher. To do so, combine 4 tablespoons of white vinegar with 4 tablespoons of baking soda and pour the mixture down your dishwasher’s drain. Let it sit for 15 minutes, then pour a cup of hot water down the drain to flush everything out. Finally, run a rinse cycle on your dishwasher to see if the clog is gone.

Some signs that your dishwasher is going out include:

• The door no longer latches 

• Dishes are still dirty after a cycle 

• Dishes are cold after a cycle 

• Rust inside or outside the unit 

• Cracks inside the dishwasher tub

• Water collecting at the bottom or outside the unit

If your dishwasher is not energy-efficient or is older than 10 years, you should also consider replacing it. Repairing an older model may be more expensive than replacing it with something newer and more energy- or water-efficient.