Satco "The Russian flight manual only states that "at temperatures of +10c or more the carb heat may be left out", whatever that means. That tends to suggest at less than +10c carb heat should be left hot."
The manual also states "Hot when outside temp is below +10C, otherwise colc, or in-between position according to outside temp".
Also " If carb icing is experienced during the descent, the throttle may become jammed. In this case, close the gills to maximise heat, ensure carb heat hot is selected, and gently try to move the throttle back and forth until the ice is broken and the throttle moves. It may be necessary to continue to make small throttle movements to prevent further jamming if icing conditions are very bad"
Lowtimer, do you not apply carb heat in a Cessna when closing the throttle for spins/landing, so why should the Yak be different.
If you experience carb icing on the ground, it will happen when airborne.