AEG L99695HWD Heat Pump Washer Dryer "Check drain filter" error whilst drying.

[randomlyAlex]

 

It's an AEG okombi 9000 Heat Pump Washer Dryer from 5+ years ago.

This washer dryer has increasingly become unreliable. 

In wash & dry mode (which are long as the heat pump dryer is slow), it will never finish a cycle.

It will interrupt with "check drain filter".  This can be "acknowledged by just pressing start again and it will continue for X time (x depending on how wet things are I feel).

Ive checked the drain, but this error is related to something else.

The drain is always fine, nothing clogged, it drains and it runs new wash cycles etc.

 

The drain motor is good, I can hear and see it working. The drains from the condenser on the heat pump are not blocked in fact I can't seem to find *anything* blocked.  I've taken it apart right down the drain at the bottom corner just to double check, hoping I'd find something...

The condenser/cold side was (like many heat pump dryers) totally full of lint, like real bad. I've cleaned that out as a mater of principle because I read of a pressure switch or the back pressure of the fan being monitored. And though maybe it was causing this.

But it just threw the same error even though it's clean as anything now.

 

Furthermore:

If I remove the piece that flows the air from drum through the heatsink on the cool side, so it just exhausts warm air to the room, it seems to be happy to continue and finish without issue.

And if I run the dryer with nothing wet inside, again, no issues in my testing.

 

So it's related to the damp air collecting and tripping something, but the error shows "check drain filter" unhelpfully.

I pressed & held start and delay, and got an error code E75, which i can't find much about with my model.

 

I'm really out of ideas. Pretty close to just using it as a washing machine only and buying a other consider dryer

 

Very happy to pay someone to fix it too tbh, but It seems pretty niche, and I don't know who'd want to look at something that doesn't have a specific error or fault that needs fixing.

[randomlyAlex]

So it's approx 2 hours into a ~4 hour cycle.  Same again. If it couldn't drain I don't know why that would be an issue now. It run a whole prewash and wash cycle. Hmm.