A tuner's other important feature is sounding a pitch. Considering that the pitch sounded is always tempered, it doesn't make sense to try to match pitches with the tuner. Then play the pitch in question and listen for beats. Beats occur whenever an interval is not in tune. They sound almost like vibrato.
Many students become so accustomed to poor intonation that they have trouble at first hearing beats.
Experimenting is the best way to train yourself to rediscover them. If you are like most clarinetists, there will likely be fast beats sounding. When the G gets low enough, the beats will slow down and stop all together. Beats get faster the further out of tune an interval is and slower as the interval gets closer to pure. When two pitches are perfectly in tune, there are no beats.