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WARNING
Before servicing or cleaning unit,
switch power off at service panel and lock the service
disconnecting means to prevent power from being
switched on accidentally. When the service disconnecting
means cannot be locked, securely fasten a prominent
warning device, such as a tag, to the service panel.
Operation
To Turn Fan ON
Turn the master switch ON.
• Fan will run at the certified airflow rate if the mode
select switch is ON.
• Fan will run at the user-adjustable airflow rate if the
mode select switch is OFF.
To Use Fan Time Delay Airflow Rate Change
1. Turn the master switch ON.
2. Turn the mode select switch ON - fan will run at the
certified airflow rate.
3. When the mode select switch is turned OFF, fan will
continue to run at the certified airflow rate until the
user-adjustable time delay has elapsed, and then will
automatically change to the user-adjustable airflow rate.
To Set the User-Adjustable Airflow Rate*
Using a small, flat-blade screwdriver, carefully rotate the
CFM adjustment until the arrow points to the desired
airflow rate.
To Set the User-Adjustable Time Delay*
Using a small, flat-blade screwdriver, carefully rotate the
TIME adjustment until the arrow points to the desired time
delay, shown in minutes.
* The user-adjustable controls are located in one corner
of the Fan Housing, behind the Grille.
ZB80L User-adjustable controls
ZB110L User-adjustable controls
To Turn Fan OFF
Turn the master switch OFF.
To Operate Lights
The light and night light can be operated independently,
using separate on/off switches.
Cleaning and Maintenance
To Clean
For quiet and efficient operation, long life and attractive
appearance, remove Grille and vacuum interior of unit
with a dusting brush attachment.
The Motor is permanently lubricated and never needs
oiling. If the motor bearings are making excessive or
unusual noises, replace the Control Assembly and Motor.
To Change Bulbs
Refer to Retrofit Installation Step 14 (page 11).
1. Carefully insert a small flathead screwdriver between
the Grille and Lens, then twist to remove Lens.
2. Purchase two (2) 18W (max.)
type GU24 fluorescent
lamps with Maximum Overall
Length (MOL) of 3.9" (100
mm). Purchase a 4W (max.)
C7-type incandescent night
light bulb.
3. Insert bulbs into their
sockets. Replace Lens.
Troubleshooting
Symptom: The fan does not run.
• Check for an open fuse or circuit breaker in the
building's service panel.
• Check that the two (2) plug-in connections for the Motor
and the Control are seated firmly in place.
• Check that the Blower Wheel spins freely.
Symptom: The fan runs erratically.
• Check that the Blower Wheel is firmly attached to the
Motor shaft and both spin freely.
Symptom: The fan seems noisy.
• Check that the back draft damper in the fan's Duct
Connector pivots freely. Screws used to attach the duct
to the Duct Connector may be preventing the damper
from opening.
• Check that the back draft damper in the wall or roof cap
pivots freely. These dampers are sometimes mistakenly
painted shut or obstructed by bird and insect debris.
Symptom: The fan does not properly ventilate the room.
• For spot ventilation, turn both the master switch and the
mode select switch ON to enable the fan to run at the
certified airflow rate.
• For spot ventilation followed by continuous ventilation,
increase the "TIME" setting of the user-adjustable time
delay.
• For continuous ventilation, increase the "CFM" setting of
the user-adjustable airflow rate.
ZB80L
ZB110L Installation Guide
n
M.O.L.
3.9" (100 mm)