What's the part called? "The Annoying Device?" I've never heard of such a thing, and my first thought is to remove it. However, I've learned to ignore my first thoughts and look stuff up before acting as it may serve a function and there may be warranty issues with modifying stuff. Still, I can't imagine why you need a hinged plastic cover on your condenser. What's it for?

Some genius invented this retrofit aftermarket hinged cover to attach to the top of the AC condenser to blow open when the fan starts. It purpose was to keep leaves out while unit was off. More problems than they are worth, take it off. Haven't seen them marketed in awhile, interest must have waned with other potential problems they have caused.

"interest must have waned with other potential problems they have caused."

It is very likely they impair air flow from the fan.

Even opening 90 degrees is not far enough to not affect air flow.

A solution in search of a problem.

That is one of them, sticking closed was even worse

I tried various things to keep leaves out but came to the conclusion that the best solution is to clean the unit once a year with a shop vac. Yeh I can imagine that cover works great with a load of snow and ice on it!