Key Takeaways
- Monthly: Clean the filter, wipe door gasket, run hot cycle with vinegar
- Quarterly: Inspect spray arm holes, check door seal condition
- Always: Use rinse aid, load correctly, run hot water before starting
- Annually: Check water inlet hose for leaks or kinks
Most dishwasher problems — dirty dishes, bad smells, leaks, and error codes — are directly linked to skipped maintenance. Unlike a washing machine or dryer, a dishwasher does its cleaning work in a sealed, heated, humid environment that is perfect for growing grease deposits, limescale, and mold if not regularly cleaned. The good news is that the maintenance routine is quick and simple.
Monthly Dishwasher Maintenance
Do These Every Month
- Remove and rinse the filter assembly under warm water
- Wipe the door gasket inside the folds with a damp cloth
- Run an empty hot cycle with white vinegar on the top rack
- Refill the rinse aid dispenser if the indicator light is on
- Wipe down the door interior and control panel
Clean the Filter — The Most Important Task
Modern dishwashers (most models made after 2010) have a manual filter that traps food particles to prevent them from recirculating during the wash. This filter sits at the bottom of the dishwasher tub, usually beneath the lower spray arm. Unlike older dishwashers with self-cleaning grinders, manual filters require regular cleaning by the user.
How to clean it: twist and lift the cylindrical filter from the bottom of the tub (most rotate counter-clockwise to release). Remove the flat mesh filter beneath it as well. Rinse both under warm running water, using a soft brush to scrub out any food debris or greasy buildup. Reassemble and lock back into place.
A clogged filter is the #1 cause of dishes coming out dirty. If your dishwasher seems to be leaving food residue on dishes after a full cycle, the filter is almost certainly the problem. Clean it before calling for a repair.
Wipe the Door Gasket
The rubber gasket that seals the dishwasher door is a prime location for mold and mildew — it traps food particles and moisture in its folds and is rarely thought about. Once a month, run a damp cloth along the full length of the gasket, pressing into the folds. Use a cloth dampened with a mild solution of water and white vinegar if you see any black mold spots. A clean gasket also seals better, preventing water leaks.
Run a Hot Cleaning Cycle with Vinegar
Place a dishwasher-safe bowl or measuring cup filled with 250 ml of white vinegar on the top rack of the empty dishwasher. Run the hottest available cycle. The vinegar disperses during the wash and dissolves grease, soap scum, and mineral deposits from the interior walls, spray arms, and filter area. You will notice the interior looking cleaner and smelling fresher after this simple monthly step.
Alternative: Commercial dishwasher cleaning tablets (Finish Dishwasher Cleaner, Affresh) can be used instead of vinegar. Do not use both in the same cycle. Run cleaning cycles on an empty machine — loading dishes at the same time reduces cleaning effectiveness on the machine interior.
Quarterly Dishwasher Maintenance
Do These Every 3 Months
- Remove and inspect the spray arms for blocked holes
- Check the door seal for cracks, tears, or hardening
- Inspect the drain area for debris beneath the filter
- Run a cleaning cycle with a commercial descaler if in a hard water area
Check the Spray Arms
Your dishwasher has at least two spray arms — one at the bottom of the tub and one mounted beneath the upper rack. Each has small holes that jet hot water onto dishes during the wash cycle. Hard water mineral deposits (limescale) gradually block these holes, reducing wash pressure and leaving dishes dirty.
Remove the spray arms by unscrewing the centre nut (lower arm) or pulling up sharply (upper arm — varies by model). Hold each arm up to the light and look through the spray holes. Use a toothpick or thin wire to clear any blocked holes. Rinse the arm under warm water, shake to clear water, and reattach. This quarterly task can dramatically improve wash performance.
Rinse Aid — Why It Matters
Rinse aid is not optional if you want spot-free dishes. It is a surfactant that lowers water's surface tension so it sheets off dishes in the final rinse rather than beading and evaporating to leave mineral spots. Without rinse aid:
- Glassware develops a cloudy film that is difficult to remove
- Dishes come out with visible water spots
- Items may still feel slightly wet at the end of the drying cycle
- In hard water areas like the GTA, mineral deposits accelerate significantly
Check the rinse aid indicator window on your dishwasher door monthly and refill when the level is low. Most dispensers hold enough for 1–3 months of normal use. You can also increase the rinse aid dosage setting in your dishwasher's settings menu if you are in a hard water area.
Loading Tips That Protect Your Dishwasher
How you load the dishwasher affects both cleaning performance and machine longevity:
- Do not block the spray arms. Large items like baking trays or cutting boards placed on the bottom rack often block the lower spray arm from rotating, leaving the upper rack dishes dirty. Check that the spray arm can complete a full rotation before starting a cycle.
- Load facing inward and downward. Cups, bowls, and containers should face the spray arm, not the door, and angled downward so water drains out.
- Do not pre-rinse excessively. Modern dishwashers are designed to work with some food residue on dishes — the detergent needs something to bind to. Scraping large chunks is fine; pre-rinsing to spotless before loading can actually reduce cleaning performance.
- Run hot water at the sink before starting. Run the kitchen tap until the water is hot before starting the dishwasher — this ensures the first fill of the machine is already at the target temperature, improving cleaning and reducing cycle time.
Annual Maintenance — Water Inlet Hose Check
Once a year, pull the dishwasher slightly away from the cabinet (or remove the kick panel at the bottom front) to inspect the water inlet hose. Look for kinks, cracks, or moisture around the hose fittings at both the machine connection and the supply valve under the sink. A small leak from a dishwasher supply line can cause hidden water damage to cabinetry and flooring over time before becoming obvious.
Also inspect the drain hose for blockages or kinks — the drain hose typically runs under the sink to the drain pipe. Ensure it forms a high loop under the sink counter to prevent drain backflow into the dishwasher.
Signs Your Dishwasher Needs a Repair
Even with good maintenance, dishwashers eventually need professional attention. Call a certified technician if you notice:
- Water pooling on the floor after a cycle — likely a door seal failure or pump leak
- Dishes consistently dirty despite a clean filter and working spray arms
- Error codes on the display (E1, E3, 7E, OE, etc.)
- Dishwasher not draining at the end of the cycle
- Unusual grinding or high-pitched humming during the wash cycle
- Door not latching properly or opening during a cycle
For dishwasher repair across the GTA, our certified technicians cover all major brands. $89 diagnostic — waived with repair.
Frequently Asked Questions
Clean the dishwasher filter at least once a month — more often if you wash heavily soiled dishes or run the machine daily. A clogged filter is the most common cause of dishes coming out dirty, with food particles redepositing on clean dishes during the wash cycle.
Place a dishwasher-safe bowl filled with 250ml of white vinegar on the top rack. Run an empty hot-water cycle. The vinegar dissolves grease, mineral deposits, and soap scum from the interior walls, spray arms, and door seal. Do this once a month.
Cloudy film on dishes is usually caused by hard water mineral deposits (limescale) or low rinse aid levels. Refill the rinse aid dispenser and run a cleaning cycle with white vinegar or a commercial dishwasher cleaner. If cloudiness persists, increase the rinse aid dosage setting.
Rinse aid is a surfactant that reduces water surface tension, helping water sheet off dishes rather than beading and leaving spots and film. It is especially important in areas with hard water like Toronto, where mineral deposits are a persistent issue. Without rinse aid, dishes and glassware will show water spots and may feel gritty.
Remove the spray arms by unscrewing the centre nut or pulling up on the arm (varies by model). Use a toothpick or thin wire to clear any clogged spray holes — hard water deposits commonly block these small openings. Rinse the arms under warm water and snap or screw them back in.
No — never put hand dish soap in a dishwasher. Hand soap creates excessive suds that will overflow from the machine and can damage the pump seals. Always use dishwasher-specific detergent tablets, powder, or gel.
A well-maintained dishwasher should last 10 to 15 years. The most common causes of early failure are a neglected filter (leading to pump damage), a worn door seal (water damage to electronics), and calcium buildup in the spray arms and inlet valve from hard water.