In article ,
"Bob Eager" writes:
Gunge - grease, fat etc. deposits are likely in internal pipes. A sod to
clear by hand but try a proprietary dishwasher cleaner (e.g. Finish do
one). You stick the bottle (has a wax seal) in the top tray and do a
wash. Repeat, possibly, if the blockage is bad.

Washing up liquid works too, but not too much or you'll have
a kitchen full of foam. There seems to be some type of grease
which dishwasher detergent allows to build up, but which
washing up liquid dissolves. (I mean real Fairy liquid here,
and not some useless Eco washing up liquid.)

I sometimes add a drip or two of Fairy liquid when putting on
the dishwasher, and I've never had any grease build-up inside
it or needed to run one of the dishwasher cleaners since
starting this some years ago.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]