(©January, 2008)
Air Technology Systems, Inc.
BNB Ultrasonic Humidifier Installation, Operation & Maintenance Manual
5-9
5.4.4 Water Supply Solenoid Valve, Float Switches and
Printed Circuit Board
1) Referring to Section “5.4.1, “Preparation for Repairs” on page 5-
7, take the water tank to a convenient place for working.
2) Cut the band bundling the solenoid valve and float switch lead
wire.
Photo 21
Note
Be careful not to damage the lead wires.
3) Remove the connecting wires of the parts to be replaced from
the terminals on the printed circuit board.
Note
Grasp the terminals when removing wires. Never pull the
lead wires.
4) Remove the float panel mounting screws and lift the float panel.
Save the screws to mount the new part.
Photo 22
5) When the solenoid valve is replaced, remove the pipe fitting
from the inlet side of the solenoid valve.
Photo 23
6) Remove the solenoid valve mounting screws.
Photo 24
7) Remove the elbow on the outlet side and install the new
solenoid valve on the outlet side. Be sure to seal the fitting with
teflon tape.
Note
Ensure the elbow is facing the correct direction.
8) Install the new solenoid valve to the float panel and re-install the
pipe fitting.
Note
Ensure the o-ring is not damaged. If it is damaged, replace
it with a new one.
9) To replace the float switch, remove the lock nut on the float
switch and replace the switch with a new one.
Photo 25
Note
Since there are two types of float switches, one type for
the water supply and one type for low water level, the type
must be checked when the float switch is replaced.
Type for water supply ............ FS1
Type for low water level .......... FS2
10) To replace the printed circuit board, remove all the lead wires
connected to the board.
11) Slide the printed circuit board out along the guides, remove it
and install a new one.
Photo 26
12) Referring to Section 5.4.2, “Re-assembling” on page 5-7,
assemble by reversing the above procedure.
