FujiFilm PB-30 Operation Manual page 42

Chapter 6 Preparation and Inspection
(7) Press the toggle switch 1 once again to deflate the balloon
by discharging air.
(8) Wrap the balloon on the endoscope lightly with your hand.
(9) Press the toggle switch 2 of the remote switch to supply
air.
(10) Make sure that the balloon inflates and the indication of
the pressure indicator is stable at about +5.6 kPa.
[Note]
The pressure indicator becomes a red display momentarily
during air feed. But, it happens by the timing of air feed
and pressure display, it is not abnormal.
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