First one I bought is 16 year old I think and the only problem is a plastic spline on the cooling fan. It made so much noise I cut it off.
So in the summer it only works for 10 mins then overheats. Leave for 30 mins and fine again. I got fed up and bought another,the old one spends its life outside to clean the dog kennel. They state 'protect from frost' that one has been outside for 3 years,the hose freezes but when thawed works fine.