Prevent "...Status maybe not OK.." from always being printed when debug is on.
Changed the is !isReady check to isPreHeating when getting the latest temperature. The isReady check prevents the function from returing the pre stored temperature within MHZxxx_RESPONSE_TIME after the UART data has been requested. This is an unnecessary restriction.
Instead of just creating an issue that the library uses a lot of memory, I wanted to save you some work instead.
I have not tested this code, but i have double checked it.