CDA FF fault codewhat it means and how to fix it
Water inlet system failure. CDA want the tap checked and the hose filter cleaned, and both are free.
Take care
What FF means
FF is CDA’s water inlet system failure, and it is the code most likely to cost you nothing. Their published remedy runs to three steps: make sure the water inlet tap is open and water is flowing, separate the inlet hose from the tap and clean the filter of the hose, and contact CDA customer care if the error continues. The middle step is the one that resolves this most often and the one almost nobody has ever done.
Where the hose screws onto the tap there is a small filter, and its job is to stop grit and scale from the mains getting into the machine. It does that job continuously for years without anyone looking at it, and eventually it does it so well that water can barely get past. Nothing in normal use prompts you to check it, and it is not mentioned in any routine maintenance most people are aware of. It takes about five minutes with a bowl. One CDA-specific caution first: the plastic housing on the inlet hose contains an electrically operated valve, with its wires running inside the hose, so CDA say never to cut the hose and never to put the housing in water. Clean the filter, not the housing.
CDA also state that the appliance is cold fill only and that a pressure relief valve is needed above 10 bar; the CDI6242 manual gives the working range as 0.03 to 1 MPa. Worth understanding too that CDA distinguish this from their other inlet-related codes. FF is the inlet system failing to deliver. F3 is the inlet failing to stop. F5 is the pressure system, meaning the machine cannot tell how much water it has. Three different problems around the same part of the machine, and the code narrows it down for you.
What causes it
| Cause | What is actually happening | How likely |
|---|---|---|
| Inlet hose filter blocked | The small filter where the hose meets the tap. CDA name it directly, and it is the cause most owners have never checked. | Common |
| Tap not fully open | CDA’s first check. Free to eliminate and worth doing properly rather than by glancing at the handle. | Common |
| Inlet hose kinked | Crushed behind the machine, which on an integrated CDA is easy to do when it goes back into the run. | Common |
| Supply pressure too low | Water arriving too slowly for the machine to complete its fill in the time allowed. The tap works, which is why this gets missed. | Occasional |
| Inlet valve failed | The valve not opening on command. What is left once the tap, hose and filter have been eliminated. | Occasional |
What to try yourself
Check the tap feeding the machine is fully open, and check any isolation valve under the sink while you are there.
Pull the machine out far enough to see the inlet hose along its length and straighten anything crushed.
Switch the machine off at the socket, close the tap, put a bowl underneath and unscrew the hose from the tap as CDA instruct. There will be water in the hose however carefully you do this.
The plastic housing at the tap end contains an electrically operated valve with its wires inside the hose. CDA say do not cut the hose and do not put the housing in water.Take the small filter out of the hose connector and clean it under a running tap. Rinse the filter only — keep the housing dry.
Refit the filter, screw the hose back on to the tap by hand, open the tap and check the joint for leaks as CDA’s installation section asks, then restore power and run a short programme.
If FF continues with the tap open and the filter clean, CDA’s instruction is to contact customer care. Tell them whether other cold taps in the house are running normally, which is the quickest indication of a supply problem rather than a machine fault.
Get a qualified appliance engineer to look at your CDA FF
We do not pass enquiries to a repair firm, so there is no form here. When you book a qualified appliance engineer, tell them the make, the model and the exact code or message on the display, and ask whether they carry parts for this make — that is what turns one visit into a repair rather than a quote.
What it costs to fix
Typical repair cost
£0–£160
Time on site
30 minutes
Usually free. A replacement inlet valve is typically £90 to £160 fitted, plus time to get an integrated machine out of the run.
Typical UK prices including parts and labour, updated September 2026. Your quote may differ.
Own this appliance and had this code? . Nothing is published until a person has read it.
Related CDA fault codes
- F3Stop — call an engineerWater is still coming in and the machine cannot stop it. Close the tap now — this is the one CDA code to act on before reading anything else.Related: water intake
- F2Get it checkedCannot discharge water. CDA mention glass shards by name in their own remedy, which is a warning as much as a diagnosis.Related: same brand
- F1Stop — call an engineerOverflow. CDA tell you to unplug the machine and close the tap — power first, then water, and the order is worth understanding.Related: same brand
- F7Get it checkedOverheating. CDA publish it as a distinct fault from their two heater codes, which tells you something about what it means.Related: same brand
- F9Get it checkedDivisor position error. The machine has lost track of the valve that decides which spray arm gets the water.Related: same brand
Own a CDA dishwasher? Save it and its codes come first next time.
Related guides
Common questions about CDA FF
Where exactly is this filter?
Inside the connector at the tap end of the inlet hose — CDA’s words are separate the inlet hose from the tap and clean the filter of the hose. Unscrew the hose from the tap and look into the fitting for a small disc, sometimes recessed enough that you need to hook it out gently. On CDA’s F-code machines that same fitting is the plastic housing with the electrically operated valve inside, so clean the filter and keep the housing out of water. It is the single most overlooked part of a dishwasher.
How often should it be cleaned?
CDA do not specify. In a hard water area every couple of years is sensible; in soft water you may never need to. Most people discover it exists at exactly this point.
My CDA shows E2, not FF. Is this my page?
No. E2 is the water inlet or supply code on CDA’s other platform — the CDI4100, CDI4200, CDI6100, CDI6200, CDI6300 and CDI6400 — and CDA’s advice there is to work through the troubleshooting tips in that manual before calling for service. The SCD4509 and SCD6011 show a long fill as the Rapid indicator flashing. This page is for the F-code models only.
What is the difference between FF, F3 and F5?
FF is the inlet system failing to deliver water. F3 is continuous water input, meaning it cannot stop. F5 is a pressure system failure, meaning the machine cannot tell how much water it has. Same area of the machine, three distinct faults.
Technical review
Not reviewed by an engineer
No engineer has read this page. Severity follows what the manufacturer publishes, and we would rather tell you that than let a byline imply a sign-off.
Sources and how we verified this
We establish the facts from the sources below and then write the explanation ourselves. We do not copy manufacturer wording and we do not host their manuals.
- Manufacturer technical and service documentation
This page has not been reviewed by an engineer, and we would rather tell you that than imply otherwise. The severity rating follows what the manufacturer publishes: where they say isolate the appliance and call someone, so do we.