When deciding whether to repair or replace your dishwasher, consider its age, the repair cost, and its warranty status. It is often worth repairing a dishwasher if it is only a few years old, the problem is minor, or the appliance is still under warranty. A common guideline is the 50% rule: if the repair cost is less than 50% of the price of a new unit, a repair is generally recommended. However, if the dishwasher is more than 10 years old or requires frequent repairs, replacement is likely the more cost-effective choice to avoid future issues. For context, a new dishwasher costs between $1,000 and $1,500 on average, while typical repairs cost several hundred dollars. Simple fixes like a damaged gasket or clogged filter can be inexpensive, but major repairs like a new pump or motor can be costly.

To clean an old dishwasher without a filter, start by removing the bottom rack to access the drain area. Use a damp cloth or sponge to wipe down the interior, paying special attention to the corners and crevices where food particles and debris can build up. Pour a cup of white vinegar into a dishwasher-safe bowl and place it on the top rack, then run a hot water cycle to help break down grease and grime. After the cycle, sprinkle a cup of baking soda across the bottom of the dishwasher and run a short hot water cycle to deodorize and further clean the interior. 

Basic maintenance, such as cleaning filters, is DIY-friendly, but repairs involving electrical components, pumps, or valves should be handled by a professional.

Local plumbing codes and manufacturer recommendations typically dictate the minimum distance between a sink and a dishwasher. This is generally 18 to 24 inches, providing enough room for easy loading and unloading of dishes without hindering the sink's function. Maintaining this separation not only adds convenience but also reduces the chances of water damage and optimizes plumbing connections.