This paper explains the drop-in test results of R410A and R32/1234ze and R32/125/1234yf blend to a R32 dedicated mini-split air conditioner as well as simulation results of them. Usually, R32 and blends are dropped in to R410A units, but here the tests were carried out in opposite direction. As the test unit employs variable speed compressor, the paper clarifies the relative performance between these refrigerants under wide range of capacity. Since 32/1234ze blend is zeotropic, the impact of the change in the flow velocity of the refrigerant in the heat exchange is clearly observed. The tests and the simulations of the sample unit are also performed at high ambient conditions with these refrigerants. Such operation is now focused on due to the Montreal protocol discussion.