Manual 2100-790
Page
42 of 49
FIGURE 16
Dirty Filter Switch Location
Dirty Filter Switch
1. Disconnect all power to the unit. Remove control
panel outer cover and upper front panel.
2. The dirty filter switch is located on top of the
filter partition to the right of the blower wheels
(see Figure 16). The dirty filter indicator light and
reset switch is attached to the side of the control
panel on the right side of the filter access opening.
Remove the cover on the dirty filter switch and
ensure the knob is set at 0.4" W.C. (see Figure
17). This is only a recommended starting point
prior to making switch adjustments. Switch setting
is highly dependent on filter type used, blower
speed, unit ducting and other unit installation
characteristics. See
Dirty Filter Switch Adjustment
for instructions on how to make proper switch
adjustments.
3. Re-install upper front panel.
Dirty Filter Switch Adjustment
1. Apply power to the unit.
2. Turn the unit indoor blower on (energize R-G on
low voltage terminal board).
3. With air filters installed and switch initially set
at 0.4" W.C. (see Step 2 under
Dirty Filter
Switch
), begin restricting the air filter of the unit
using a piece of cardboard under the filters until
the switch trips and the light comes on. If the
filter is restricted by 75% (or desired restriction
amount), skip to Step 6.
4. If switch setting adjustment is required,
disconnect power to the unit. Remove the upper
front panel and the cover on the airflow switch so
that adjustment can be made. If the switch tripped
before 75% restriction was reached, turn the knob
slightly clockwise. If the switch tripped after 75%,
turn the knob counter-clockwise (see Figure 17).
5. Replace the upper front panel and repeat Steps
1-3. Continue to make adjustments described in
Step 4 until the desired restriction is obtained.
6. Remove the restriction and reset the filter switch.
Replace the switch cover once adjustment is
complete.
7. Install the outer control panel cover. This
completes the adjustment.
