The short version
A dishwasher that washes badly is usually being starved of something rather than broken: water, heat, detergent contact or spray coverage. The order below is the order in which those four go wrong. On an F&P dishwasher the place to start is the water temperature and the fill level, because an integrated machine will not proceed until its own sensing says it may, so the control and sensing chain outranks the pump.
What the machine is doing
- Detergent still sitting in the dispenser at the end — The dispenser never opened, or an item in the rack blocked it from opening.
- Grit left on the underside of bowls and plates — Spray is not reaching the lower rack, or the filter is returning debris into the wash.
- A chalky white film on glasses — A hardness or rinse-aid problem rather than a mechanical one, and it looks nothing like grit.
- NEAR MISS: dishes are clean but soaking wet — That is a drying complaint, not a washing one, and it has its own causes.
The causes, ranked for this brand
- Not enough water, or not hot enough water — Detergent needs heat to work and coverage to reach. Ranked first on an F&P dishwasher: this platform sits behind a sensing layer that decides what the machine may do next, so what the sensors believe explains the symptom far more often than a failed part does.
- A loaded filter recirculating its own debris — The filter bowl catches what comes off the dishes, and once it is full the pump draws through the debris and puts it back on the load. Where it sits here: the most common cause of a dishwasher that has gradually got worse, and the one owners are least likely to have checked.
- Loading that blocks the spray arms or the dispenser — A tray laid flat across the lower rack, a tall pot in the wrong slot or a large lid over the dispenser all stop the machine doing what it is designed to do. Where it sits here: free to correct and unusually common, which is why it belongs near the top rather than as an afterthought.
- Blocked spray-arm jets or an arm that will not turn — Each jet is a small hole and each one silts up with hard-water scale and food debris. Where it sits here: ranks higher wherever the water is hard, because scale closes those jets from the inside out.
What to check first, and why that order
- Start at the water temperature and the fill level — It is the cause that ranks first on this kind of machine, so it is the check that ends the diagnosis most often and the one that costs least to make.
- Pull the filter out and look at it — Thirty seconds, no tools, and it settles the most common cause outright.
- Spin both spray arms by hand — They should turn freely through a full circle with nothing catching.
The checks you can make yourself
- Clear the spray-arm jets — Take each arm off, flush it under the tap, and open blocked holes with a toothpick or a piece of wire from the outside.
Tools: toothpick, small wireAbout 20 min
- Run a hot empty cycle with a cleaner — A dishwasher cleaner or plain white vinegar in the dispenser, hottest cycle, no load.
Tools: dishwasher cleanerAbout 90 min
- STOP HERE if the water never gets hot — Testing a heating element or a thermostat means a meter on a live or dismantled circuit, and that is where the owner checks end.
Before you touch it
Safety
Switch the machine off at the wall or its breaker before reaching into the sump; a capacitor can hold a charge after the power is off, and there is a chopper or an impeller down there on many machines. Never mix a dishwasher cleaner with bleach, and never put washing-up liquid in the dispenser: the foam it makes will push water out of the door seal and onto the floor.
Where the owner job ends
Call once the filter, the arms and the loading are all proven good and the wash is still poor, or when the water is not getting hot on a cycle that should be hot. A circulation pump that is running weakly sounds normal and washes badly, and it is the one cause on this list that needs a technician to name with any confidence.
Related pages in this set
What is deliberately not here
This page covers F&P dishwashers as a class, not one family or model line. Where a family- or model-specific page exists for your unit, that is the more specific answer and the one to read first. Deliberately not here: spray-arm part numbers, element ratings and detergent dosing tables, all of which differ by family.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
