Installing The Thermostat - Honeywell Prestige IAQ YTHX9421 Installation Manual

2

Installing the thermostat

2.1 Separate wallplate
from thermostat.
2.2 Mount wallplate as shown.
Mount new wallplate using
screws and anchors included
with the thermostat.
Drill 3/16-in holes for drywall.
Drill 7/32-in holes for plaster.
2.3 Connect power to
thermostat.
2.3a Connect thermostat to
the R and C terminals at
the EIM or to a separate
24 volt transformer (not
provided).
2.3b Push excess wire back
into the wall opening.
2.4 Insert coin cell battery.
Place coin cell battery in
thermostat as shown with +
side up.
NOTE:
Coin cell battery saves
time and date during a power
loss.
Thermostat (back view)
1324
Thermostat (back view)
6
Wallplate (back view)
Wallplate
R
C
Wallplate
Coin cell
battery
1324