PLA has quite a low glass point - where it starts to melt, and it is also a biodegradable material, so using it in any wet or high humidity will considerably reduce the life span.

Not sure on your printer, but ABS or some of the PET / PET-G materials might be better suited. These will stand more abuse.

Not sure why you needed to wash the parts though. Mine generally just need a quick brush over and with ABS, a quick sand to remove the occasional string.