Carrying a portable air conditioner

I have a very old air conditioner that I install in my bedroom window every year.  Although the air conditioner is a portable unit, it is extremely large and heavy.  I store the cooling unit in the attic.  I haul it down the stairs in the beginning of May, and I carry it back up at the end of September.  While I enjoy having an air conditioned bedroom, the moving process is really challenging.  The attic stairs are super narrow and steep, with very shallow steps that curve around.  The air conditioner barely fits, and I need to carefully maneuver, while trying not to fall.  After I manage to wiggle the air conditioner through the tight doorframe, I must carry it down a long hallway to my bedroom.  The cooling unit barely fits into the window, and I always end up sweaty and with a sore back by the end of the process.  Once the air conditioner is in place, it is a simple matter of plugging it in and turning it on.  Despite the age and bulk of the cooling unit, it runs very quietly and efficiently.  It costs me little to run and keeps my bedroom perfectly cool all summer long.  I often consider purchasing a new air conditioner, just to avoid the difficulty of carrying it up and down the stairs.  I am reluctant to replace the air conditioner when it is still working just fine.   I am not convinced that modern equipment is made as well as my old cooling system.  I need to find a place to store the cooling system that would be more convenient.

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