Lamona HJA8630 dishwasher will not drain when a cycle is run

Summary – Lamona HJA8630 dishwasher will not drain when a cycle is run but will force drain if drainage pump is disconnected then reconnected.

I have a Lamona HJA8630 dishwasher. When I run any cycle the dishwasher will run through the cycle but will not drain at the end. When I try a force drain the drainage pump will make a low growling noise but the machine won’t drain. At first I thought the drainage pump was broken but when I disconnect the pump and then reconnect the pump the force drain works. However, when I go to a run a cycle the initial problem occurs and the machine will not empty. Any idea why this might occur and how it might be fixed?

I’ve worked through the fault finding guide and I’ve run the dishwasher error checker (hold start + program 3secs at startup) but the dishwasher displays no error.

Cheers!