If your neighbor's dishwasher is not making any noise, there are several ways you might be able to tell if it's broken or experiencing an issue:
No lights or display: Check if the dishwasher's control panel lights are not turning on or if there is no display. A lack of power to the dishwasher could indicate an electrical problem or a malfunctioning control board.
Water leaks: If you notice water pooling around the dishwasher or seeping out from under it, it could be a sign of a broken hose, pump, or water inlet valve.
Door issues: If the dishwasher door doesn't close properly or won't latch securely, it could prevent the dishwasher from starting its cycle.
Dishes not cleaned properly: If you can see inside the dishwasher and notice that the dishes are not coming out clean after a cycle, it might indicate a problem with the spray arms, water circulation, or the dishwasher's detergent dispenser.
Foul smells: A broken dishwasher that has standing water inside or is not draining correctly may produce foul odors over time.
Error codes (if visible): Some dishwashers have digital displays that show error codes when there's a problem. If you can see the front of the dishwasher, look for any error codes that might be displayed.
Visual inspection: If you have a clear line of sight into your neighbor's kitchen and can see inside the dishwasher, check for any visible signs of damage or malfunction.
It's important to note that even if the dishwasher is not making any noise, it may not necessarily be broken. Some modern dishwashers are designed to run quietly, and the absence of noise might not indicate a problem. However, if you notice any of the above signs, it's possible that the dishwasher may be experiencing an issue that requires attention or repair.
If you suspect your neighbor's dishwasher is broken, it's best to communicate with them politely and let them know about your observations. They may not be aware of the problem, and informing them can help them take appropriate action, such as contacting a repair service or the manufacturer for assistance. Respect their privacy and try to be helpful in resolving the situation if they need assistance.