Honeywell CT3400

17 69-0733B—1
■ Remove wallplate from wall, and drill
3/16 inch holes in wall (if drywall) as marked.
For firmer material such as plaster or wood,
drill 7/32 inch holes. Gently tap anchors
(provided) into drilled holes until flush with the
wall.
■ Reposition wallplate over holes, pulling
wires through wiring opening. Loosely insert
two mounting screws into holes.
■ Level for appearance only; thermostat will
function properly even when not level. Tighten
mounting screws.
M611A
SPIRIT LEVEL
INSTALLATION
18 69-0733B—1
STEP 6 Adjust System On-Length, Clock Display, As
Required
■ The thermostat on-length is factory-set for
a warm air, gas or oil heating system. If you are
installing it on another type of system, the on-
length must be adjusted accordingly by setting
screws 1A and 1B on the back of the thermo-
stat, using the heating system table in the
figure as a guide. The on-length should be
optimized with the type of system to minimize
room temperature swings. Setting the screw out
one turn means turning the screw approxi-
mately 360°, or about one complete turn.
In the rare event that you want a longer on-
length, you may readjust the screws as follows,
but be aware that you may be increasing room
temperature swings at the same time.
If on-length screws 1A,1B are adjusted For longer on-length, readjust
to match this system: screws 1A,1B to match this system:
electric warm air gas/oil warm air
gas/oil warm air hot water or high efficiency
hot water or high efficiency gravity air/water