6 W43A Humidistat Product/Technical Bulletin
!
CAUTION: Equipment damage hazard.
Avoid contact with human hair
sensing element. Contact with
hair element can affect control
accuracy and/or product life.
4. While holding the dial firmly in place, keeping the
setting in line with the calibrating mark, depress
the tab “B” (see Figure 9) and rotate it clockwise
until it is against the stop pin “C”.
5. Release the tab making sure it fits into the nearest
notch.
6. Replace the humidistat cover, tighten the bottom
cover screw, and replace the adjustment knob.
7. Rotate adjustment knob to desired normal
operating setpoint.
HUM
OF
F
DE
H
OF
F
70
50
40
30
20
10
Stop Pin "C"
High Range
Stop Tab "A"
Calibrating
Mark
Sensing
Element
Low Range
Stop Tab "B"
Figure 9: W43A Humidistat Range Tabs and Stop
D
ial Lock
The high range stop and low range stop can be set to
keep the adjustment knob from rotating. To lock the
dial:
1.
Set the adjustment knob to the desired RH setting.
2.
Pull the adjustment knob off the humidistat cover.
3.
Loosen the bottom cover screw and remove the
humidistat cover.
!
CAUTION: Equipment damage hazard.
Avoid contact with human hair
sensing element. Contact with
hair element can affect control
accuracy and/or product life.
4.
While holding the dial firmly in place, keeping the
setting in line with the calibrating mark, depress
the tab “A” and rotate it counterclockwise until it is
against the stop “C”. Depress the tab “B” and
rotate it clockwise until it is against the stop
pin “C”. See Figure 9.
5.
Make sure each tab fits into the notch closest to
the stop.
6.
Replace the humidistat cover, tighten the bottom
cover screw, and replace the adjustment knob.
C
heckout Procedure
Before applying power, make sure installation and
wiring connections are according to job specifications.
After all necessary adjustments and electrical
connections have been made, put the system into
operation and observe at least three complete
operating cycles before leaving the installation.
R
epairs and Replacement
Field repairs must not be made except for replacement
of the adjustment knob or mounting plate. Refer to
Table 4: Replacement Parts
for replacement part
ordering information. For a replacement W43A,
contact the nearest Johnson Controls representative.
