42
C
OOLING
O
PERATION
WITH
A
C
OMMUNICATING
T
HERMOSTAT
AND
C
ONVENTIONAL
S
INGLE
S
TAGE
A/C
•
The call for cooling will be communicated via the
ClimateTalk™ protocol.
•
The Y1 terminal of the IFC becomes an output via the
on board Y1 relay
•
The IFC does not provide short cycle protection.
•
The circulator operates as commanded by the com-
municating thermostat.
C
OOLING
O
PERATION
WITH
A
C
OMMUNICATING
T
HERMOSTAT
AND
O
UTDOOR
U
NIT
•
The furnace receives the CFM demand from the com-
municating outdoor unit.
C
ALL
FOR
C
OOL
WITH
C
ALL
FOR
H
EAT
P
RESENT
– D
UAL
F
UEL
D
EFROST
O
PERATION
•
While in defrost, the standard light off sequence will
be followed. The IFC will then fire at 100% for the
remainder of the defrost call.
•
While in defrost the circulator will use the selected
heat speed.
F
AN
M
ODE
C
ONVENTIONAL
T
HERMOSTAT
Two seconds after G request becomes active without Y1
request, IFC will run the circulator at the appropriate speed
(as selected by the DIP switches), unless circulator is run-
ning as a result of Heat or Cool mode. The circulator speed
required by the heat or cool demand always has priority
over G speed.
C
OMMUNICATING
T
HERMOSTAT
If a conventional G request is present without a heat or cool
request from the communicating thermostat, the circulator
will run at the selected fan speed.
H
UMIDITY
C
ONTROL
H
UMIDIFIER
O
UTPUT
– C
ONVENTIONAL
T
HERMOSTAT
One set of isolated relay contacts are wired to a pair of
terminals for connection to a humidifier. When the inducer
is on the IFC closes the humidifier relay contacts, except
from the calibration routine where the humidifier relay con-
tacts are always open.
H
UMIDIFIER
O
UTPUT
– C
OMMUNICATING
T
HERMOSTAT
One set of isolated relay contacts are wired to a pair of
terminals for connection to a humidifier. Upon receipt of a
Humidification Requested Demand the IFC will:
•
Close the humidifier relay contacts
•
Energize the circulator at the circulation speed (G
speed) unless the circulator is commanded to a dif-
ferent speed by a heat demand.
D
EHUMIDIFICATION
– C
ONVENTIONAL
T
HERMOSTAT
•
DEHUM functionality is enabled by a DIP switch set-
ting.
•
The IFC varies circulator speed operation based on
the DEHUM signal from the thermostat
•
If 24VAC (R) is not connected to DEHUM (through a
Humidistat) and both Y1 and O terminals are ener-
gized, then the IFC control reduces the cooling CFM
by 15%.
•
If both Y1 and O terminals are not energized, the
DEHUM signal is ignored
•
DEHUM is ignored during any heating request.
L
EARN
P
USH
-B
UTTON
Pressing the learn button re-sets the communicating net-
work and allows the IFC to search for communicating equip-
ment The press and release of the button starts the same
learning process as during power-up of the system.
C
LIMATE
T
ALK
™ C
OMMUNICATION
LED
S
The IFC has two LEDs :
•
Red communications LED – Indicates the status of
the network
•
OFF is normal condition.
•
2 slow flashes on power-up: ON for ¼ second, OFF for
¾ second, ON for ¼ second, OFF.
•
Continuous slow flash indicates communication fail-
ure: ON for ¼ second, OFF for ¾ second…
•
Green receive LED – Indicates network traffic
•
Fast, sporadic flashes indicates normal bus commu-
nication.
•
ON solid indicates a Data 1 / Data 2 miswire.
OPERATION
