TM 9-2320-209-10-1 c. Operating the Exhaust Blower. (1) Operating from 24-volt source FRAME 1 1. Place POWER SWITCH 115-VAC (1) handle in OFF (down) position. 2. Place converter SELECTOR switch (2) in 24V position. 3. Place EXH BLOWER switch (3) in desired HI or LOW speed position. 4-210