M6113
1
L1
(HOT)
L2
5 R
C
4 W
6
Y
1
2
3
4
5
6
7
8
1
L1
(HOT)
L2
5 R
C
4 W
6
Y
CW
(OPEN)
COM
CCW
(CLOSED)
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
VVO BD
DAMPER
CDO-52
VVA RD
DAMPER
VVT (T641A)
OR
VVT-HC (T641C)
Settings
TEMPERATURE SETTING
Move the heating and cooling set point levers to the
desired comfort positions. See Fig. 3.
SWITCH SETTING
The VVT-HT (T641C) has a manual heat/cool changeover
switch. With this switch set in the cool position, wire to
damper actuator as shown in Fig. 4. Be sure to determine
direction of damper opening for correct wiring between the
thermostat and the actuator. The changeover switch can be
placed in the heat position to reverse action at terminals 4 (W)
and 6 (Y).
Checkout
With the VVT (T641A) or VVT-HC (T641C) Thermostat
controlling the damper or equivalent actuator, lower the set
point of the thermostat to call for cooling. Observe the
operation of the motor. If the damper is closed, it should begin
to open. If not, adjust the set point of the thermostat higher to
determine if the wiring is correct. If no movement is ob-
served, check for the presence of 24 Vac between terminals
of the motor during a call for cooling. With the proper wiring
and 24 Vac present, the actuator should operate correctly. If
24 Vac is not present on a call for cooling, replace the
thermostat.
To check out the damper when controlled by the thermo-
stat, determine the direction the damper shaft moves to open
the damper. Place 24 Vac across the appropriate common and
open terminal to energize the actuator after disconnecting the
external wires. The damper should begin to open the damper.
If the motor does not run, try switching the 24 Vac across the
opposite terminals to determine if the damper will begin to
close. Replace the damper if the motor does not run in either
direction.
Fig. 4—Dampers used with VVT (T641A) and VVT-HC (T641C) Thermostats for Type B damper applications.
Y terminal energizes counterclockwise (ccw) winding on call for cooling, driving motor open.
HONEYWELL TROL-A-TEMP
57 BUSHES LANE • ELMWOOD PARK, NJ 07407-3204
TELEPHONE: 201-794-8004, 800-828-8367 • FAX: 201-794-1359
PRINTED IN MEXICO