What should the clearances around a heatpump/air conditioner be?

I would go no less than 14- 18 inches.

If you set it any closer it makes it hard on the fellow that has to work on in the future, especially if he`s a rather large person like me,cause usually the contacter,capicitor and such is closest to the wall

What should the clearances around a heatpump/air conditioner be?

There is a very specific answer in the install instructions that came with the unit. Some require 30 inches or more depending upon required access.