I have a Bosch WTG86400UC ventless dryer whose sump pump doesn't drain. I put a cup of water in the basin, and it remains there throughout the cycle.
I noticed a couple of years ago that the sump reservoir had standing water and attributed that to lint build up that might have clogged the hose or pump. I've cleaned the condenser several times since then. But it's possible that the pump never worked properly
I think the motor is working ok. I tested it outside of the machine and it spins normally.
I'm thinking it might be a sensor issue. This model doesn't have a float but appears to have a couple of probes next to the motor that sense the presence of water in the basin. There might be another sensor that I can't see which would also control power to the motor
Any ideas? Thanks