My 13 year old 1604 has had one damper in its very busy life. The tech that replaced the head 8 years ago (still a perfect nozzle test) insisted unless their was a problem on the dampers only replace when needed.
I have found the best thing for these machines is to use them a lot. The more you use them the more reliable they are.
Currently got a 1614 to reinstate which looks like it has a harder life or more than likely run by operatives that did not have any idea on running these machines.
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