Carrier bryant 830CA, Руководство пользователя

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830CA: Installation, Start–Up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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a. When the R-to-Y1 circuit is closed, R-to-G circuit is open, and
there is a demand for dehumidification, the furnace blower motor
BLWM will drop the blower airflow to 65 percent of low-cooling
airflow for a maximum of 10 minutes each cooling cycle or until
the R-to-G circuit closes or the demand for dehumidification is
satisfied. Low-cooling airflow is the true on-board CF
(continuous fan) selection as shown in Fig. 45 .
b. When the R-to-Y/Y2 circuit is closed, R-to-G circuit is open, and
there is a demand for dehumidification, the furnace blower motor
BLWM will drop the blower airflow to 65 percent of
high-cooling airflow for a maximum of 10 minutes each cooling
cycle or until the R-to-G circuit closes or the demand for
dehumidification is satisfied. High-cooling airflow is based on
the A/C (air conditioning) selection shown in Fig. 45 .
c. When the “call for cooling” is satisfied and there is a demand for
dehumidification, the cooling blower-off delay is decreased from
90 seconds to 5 seconds.
5. Continuous Blower Mode
When the R-to-G circuit is closed by the thermostat, the blower
motor BLWM will operate at continuous blower airflow.
Continuous blower airflow selection is initially based on the CF
(continuous fan) selection shown in Fig. 45 . Factory default is
shown in Fig. 45 . Terminal EAC-1 is energized as long as the
blower motor BLWM is energized.
During a call for heat, the furnace control CPU will transition the
blower motor BLWM to continuous blower airflow, heating airflow,
or the mid-range airflow, whichever is lowest. The blower motor
BLWM will remain ON until the main burners ignite then shut OFF
and remain OFF for the blower-ON delay (25 seconds in heat),
allowing the furnace heat exchangers to heat up more quickly, then
restarts at the end of the blower-ON delay period at heating airflow.
The blower motor BLWM will revert to continuous-blower airflow
after the heating cycle blower off-delay is completed.
When the thermostat “calls for low-cooling”, the blower motor
BLWM will switch to operate at low-cooling airflow. When the
thermostat is satisfied, the blower motor BLWM will operate an
additional 90 seconds at cooling airflow before transitioning back
to continuous-blower airflow.
When the thermostat “calls for high-cooling”, the blower motor
BLWM will operate at high cooling airflow. When the thermostat is
satisfied, the blower motor BLWM will operate an additional 90
seconds at high-cooling airflow before transitioning back to
continuous-blower airflow. When the R-to-G circuit is opened, the
blower motor BLWM will continue operating for an additional 5
seconds, if no other function requires blower motor BLWM
operation.
a. Continuous Blower Speed Selection from Thermostat To
select different continuous-blower airflow from the room
thermostat, momentarily turn off the FAN switch or push button
on the room thermostat for 1-3 seconds after the blower motor
BLWM is operating. The furnace control CPU will shift the
continuous-blower airflow from the factory setting to the next
highest CF selection airflow as shown in Fig. 45 . Momentarily
turning off the FAN switch again at the thermostat will shift the
continuous-blower airflow up one more increment. If you repeat
this procedure enough you will eventually shift the
continuous-blower airflow to the lowest CF selection as shown in
Fig. 45 . The selection can be changed as many times as desired
and is stored in the memory to be automatically used following a
power interruption.
NOTE: If the blower-off delay is set to the maximum (SW1-7 and 8 are
ON), the adjustable continuous-fan feature is locked (i.e., fan speed
cannot be changed from its current setting).
6. Heat pump
See Fig. 28 or Fig. 29 for thermostat connections.
When installed with a heat pump, the furnace control automatically
changes the timing sequence to avoid long blower off times during
demand defrost cycles. Whenever W/W1 is energized along with
Y1 or Y/Y2, the furnace control CPU will transition to or bring on
the blower motor BLWM at cooling airflow, heat airflow, or the
mid-range airflow, whichever is lowest. The blower motor BLWM
will remain on until the main burners ignite then shut OFF and
remain OFF for 25 seconds before coming back on at heating
airflow. When the W/W1 input signal disappears, the furnace
control begins a normal inducer post-purge period while changing
the blower airflow. If Y/Y2 input is still energized the furnace
control CPU will transition the blower motor BLWM airflow to
cooling airflow. If Y/Y2 input signal disappears and the Y1 input is
still energized the furnace control CPU will transition the blower
motor BLWM to low-cooling airflow. If both the Y1 and Y/Y2
signals disappear at the same time, the blower motor BLWM will
remain on heat airflow for the selected blower-OFF delay period.
At the end of the blower- OFF delay, the blower motor BLWM will
shut OFF unless G is still energized, in which case the blower
motor BLWM will operate at continuous blower airflow.
7. Component test
The furnace features a component test system to help diagnose a
system problem in the case of a component failure. To initiate the
component test procedure, ensure that there are no thermostat
inputs to the control and all time delays have expired. Turn on setup
switch SW1-6, see Fig. 25 .
NOTE: The component test feature will not operate if the control is
receiving any thermostat signals or until all time delays have expired.
The component test sequence is as follows:
a. The furnace control CPU turns the inducer motor ON at 50%
torque and keeps it ON through step c.
b. After waiting for 15 seconds of inducer only operation, the
furnace control CPU turns the hot surface igniter ON for 15
seconds, then OFF.
c. The furnace control CPU then turns the blower motor BLWM on
at mid-range airflow for 15 seconds, then OFF.
d. After shutting the blower motor OFF the furnace control CPU
switches the inducer OFF .
NOTE:
The EAC terminals are energized when the blower is operating.
After the component test is completed, 1 or more status codes (11, 25,
41 or 42) will flash. See component test section or Service Label
( Fig. 39 ) for explanation of status codes.
NOTE:
To repeat component test, turn setup switch SW1-6 to OFF and
then back ON.
Wiring Diagrams
Refer to Fig. 45 for wiring diagram.
Troubleshooting
Refer to the service label. ( Fig. 39 ), and wiring diagram ( Fig. 45 ) can be
a useful tool in isolating furnace operation problems. The Guide will
help to identify the problem or failed component. After replacing any
component, verify correct operation sequence.