Thanks for the input. The sink drain flows freely. The drain hose enters the sink cupboard unit at low level and rises to the appliance trap but I can't see if the rest of the hose behind the dishwasher is raised before dropping as it's an integrated dishwasher in a rented property. But it...
This is a weird dishwasher plumbing question. A Neff dishwasher that was here when we moved in just started not draining at the end of the washcycle - i.e. standing water in the base. It only happened on the four longest cycles not the 30 minute quick wash option. So I checked the obvious...
