Honeywell CHRONOTHERM T8624C - Manual (Page 6)

6
T8624C,D
INSTALLATION
Fig. 4—Mounting subbase on wall.
WIRES THROUGH
WALL OPENING
WALL
WALL
ANCHORS
(2)
SUBBASE
MOUNTING
HOLES
MOUNTING
SCREWS (2)
M846
Fig. 5—Restrict wiring to recessed area
surrounding terminals.
FOR STRAIGHT
INSERTION –
STRIP 5/16 in. [8 mm]
FOR WRAPAROUND –
STRIP 7/16 in. [11 mm]
RESTRICT
WIRING TO
THIS AREA
WIRING TO BE BELOW
THIS SURFACE TOP SURFACE
OF SUBBASE
FRONT VIEW OF
TERMINAL AREA
CROSS-SECTIONAL VIEW OF
TERMINAL AREA
M 847
WIRING
All wiring must comply with local electrical codes
and ordinances.
Disconnect power before wiring to prevent electrical
shock or equipment damage.
The shape of the terminal barrier permits insertion of
straight or conventional wraparound wiring connections.
Either method is acceptable.
Push excess wire back into the hole, and plug the hole
with nonhardening caulk, putty or insulation to prevent
drafts from affecting thermostat operation.
NOTE: Restrict wiring to the recessed area surrounding
the terminals (Fig. 5) to assure thermostat/subbase
contact.
Refer to Figs. 6-8 for typical hookups of subbase and
thermostat.
ADJUSTING CYCLE RATE
To customize the thermostat cycling performance to
various types of heating equipment, cycle rate adjust-
ment screws are provided on the back of the thermostat
to provide optimum room temperature control.
NOTE: Most applications will not require a change in
cycle rate.
The room air temperature will normally vary slightly
from the comfort temperature setting with the cycling of
the furnace or air conditioner.
The heating cycle rate of this thermostat is factory-set
for gas/oil warm air heating. The cooling cycle rate is
factory-set and cannot be adjusted. The heating cycle
rate can be adjusted by turning one or both cycle rate
adjustment screws located on the back of the thermostat.
In multistage heat systems, the cycle rate adjustment
applies to the highest stage of heat only. Screws should
be backed out about one-half to one turn, or be turned in
until tight. See Fig. 9.
TIME/TEMPERATURE CONVERSION
(SOME MODELS)
The display readout may be converted between 12
and 24 hour clock or
°
C and
°
F using screws 2A and 2B
as indicated in Fig. 9.
FAN OPERATION OPTION SWITCH
(SELECT MODELS ONLY)
Select models include a fan operation option switch
on the subbase that is visible before the thermostat is
mounted on the subbase. The switch should be in electric
heat position for electric heating systems that do not
have independent fan control.
INSTALLING BATTERIES
Three AAA alkaline batteries are included to provide
backup to prevent program loss in case of power outage.
Install batteries in back of thermostat as shown in Fig.
10.
Without battery backup, the program will remain
about 30 seconds in event of power loss.
IMPORTANT: When batteries are first installed, the
display will flash 1:00 PM and 32
°
. The tempera-
ture will stay at 32
°
F until the thermostat is
powered from the system wiring.
When the batteries are low, the display will flash
REPL BAT. Homeowner will have 20-30 seconds to
install new batteries after removing old batteries from
back of thermostat. After 20-30 seconds, it will be nec-
essary to reprogram. REPL BAT indication will disap-