Adjusting Cycle Rate - Honeywell T8621A User Manual

WIRES THROUGH
WALL OPENING
WALL
ANCHORS
(2)
Fig. 2—Mounting subbase on wall.
FOR STRAIGHT
INSERTION –
STRIP 5/16 in. (8 mm)
RESTRICT
WIRING TO
THIS AREA
FRONT VIEW OF
TERMINAL AREA
KEEP WIRING BELOW
THIS SURFACE
CROSS-SECTIONAL VIEW OF
TERMINAL AREA
Fig. 3—Restrict wiring to recessed area surrounding
terminals.
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 hole with
nonhardening caulk, putty or insulation to prevent drafts
from affecting thermostat operation.
WALL
MOUNTING
HOLES
MOUNTING
SUBBASE
SCREWS (2)
M846
FOR WRAPAROUND –
STRIP 7/16 in. (11 mm)
TOP SURFACE
OF SUBBASE
M847
Refer to Figs. 4-9 for typical hookups of subbase thermo-
stat.
NOTE: Restrict all wiring to recessed area surrounding
terminals (Fig.3) to assure thermostat/subbase contact.

ADJUSTING CYCLE RATE

To custom-tailor the thermostat's cycling performance
to different types of heating equipment, cycle rate adjust-
ment screws are provided on the back of the thermostat.
Correct setting of these screws will provide optimum room
temperature control.
NOTE: MOST APPLICATIONS WILL NOT REQUIRE A
CHANGE IN CYCLE RATE.
HIGH
LIMIT
SYSTEM
SWITCH
HEAT
AUTO
COOL
OFF
FAN
SWITCH
AUTO
ON
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
2 FOR SINGLE TRANSFORMER SYSTEM JUMPER R AND RC.
3 NOMINAL 24 Vac POWER MUST BE PRESENT BETWEEN R AND C FOR
THERMOSTAT OPERATION.
Fig. 4—T8621A 1-stage heat/1-stage cool thermostat
with HEAT-AUTO-COOL-OFF system and
AUTO-ON fan switching.
2
HEATING
TRANSFORMER
R
2
3
POWER
C
SUPPLY
H HEAT RELAY
W1
C
Y1
COOLING
CONTACTOR
G
FAN RELAY
2
RC
COOLING
TRANSFORMER
1
L1
(HOT)
L2
L1
(HOT)
L2
1
M1574