Perfect advice thanks - signed up just to add some google hints for anyone else with the same problem.
Had a few power issues with sockets for washing machine and dish washer, both stopped mid-cycle.
Reset Hotpoint Aquarius DWF 30 using end program two button cycle. Then restarted. Stayed on end program for way too long.
Many power cycles etc later and still sounded like it was just trying to drain out water - no water in machine. Added a few jugs worth, still stuck.
Took advice above, removed right hand side, drained out water in the base, bit worrying, all those cables and waste water in the base, anyway, drained out and restarted, end program finished and now working fine.
Google keywords below :
DWF 30 Hotpoint stuck draining water never ending