Sounds like it but I could be wrong
Those are sealed units just like a refrigerator or a window style unit. You can recharge them with some effort. They hold very small amounts of refr. so if it has lost the charge there is a leak that has to be found and repaired.
That said, most often the merely require a good cleaning inside and they run fine again. There could be other issues. If you could get it to me I would gladly look it over for you.