My bed room is installed with a split air conditioner, not satisfied with the cooling.?

In the case of the air conditioners, the tonnage capacity of the conditioner is directly proportional to the room size. Assuming the room size to be 12X12. You need a 1.5 ton capacity A.C. The best company manufacturing A.C.s is daikin, ogeneral and hitachi. All others are almost 75% of the best. Further, if ur living conditions is really hot, you need to have the false ceiling installed in the room for retaining of the coolness. Check out if u have any big metal items( like almirah) in the room. Since, they absorb coolness they should be avoided. Check out that the rooms is concealed. ....If everything of the above is right, you should feeling like heaven.

Sounds like the unit is undersized, in summer the machine is struggling to bring the the space temperature down to set point. Do you have the bedroom door open at night? This will add to the ability of the machine to work effectively.

Alternatively maybe the unit does have a problem, possibly with the gas charge, but as the installer has been back several times it seems unlikely that this would be the case. Didn't the "company man" offer some sort of explanation??

Hope this helps

More than likely it is poor duct work design. It is easier to move hot air which is light than cool air which is heavier. That is why you don't have a problem with heating. I would guess that the return air is inadequate. You didn't mention if your bedroom is on the first or second level. If it is on the second level, close some downstairs registers to force more air upstairs in the summer. Reverse in the winter.