Installation
n
3.12
Comfort Plus
AUXILIARY LOAD CONTROL
The Comfort Plus can be used to provide control signals to
other loads in the application. To do so, connect low voltage
control wires to the "COM" and "NC" or the "COM" and
"NO" positions of the low voltage terminal block in the
electrical compartment of the Comfort Plus system. (See
Figure 17.) These contacts are rated for 30 volts, 3 amps
maximum.
Installation
HUMIDIFIER/ELECTRONIC FILTER INSTALLATION
The Comfort Plus is capable of being connected to a humidifier and/or an electronic air filter. If installing either
of these devices, connections to the Comfort Plus system are made to the bottom two relays on the base I/O
relay board inside the system's electrical panel. Refer to the Line Voltage Wiring Diagrams (Page A.09-A.12)
for the location of these relays.
If installing a humidifier, connect it to the "HEAT CALL" relay on the base I/O relay board. This relay closes
during a heat call.
If installing an electronic air filter, connect it to the "FAN ON" relay on the base I/O relay board. This relay
closes during a fan call. The maximum filter size if using a Steffes Return Air Plenum is 20" x 25" x 2.
Maximum external load should not
exceed 60 VA on the system's class
II transformer.
IMPORTANT
TWO STAGE HEAT PUMP APPLICATION WITH VARIABLE SPEED BLOWER
FIGURE 16
TYPICAL AUXILIARY LOAD CONTROL
FIGURE 17
NOTE: During off-peak (charge) periods, the con-
tact is closed between "COM" and "NC".
W/
NO
NC
COM
Ou
td
oo
r
Ou
td
oo
r
C
R
H/E
Y2
Y1
AUX
O
G
RP
2
2
Y1 Y2
2
O
AP
P
Inputs
Peak
Aux.
Relay
Auxiliary Control Relay
Relay Contacts
Relay Coil
COM
NO/NC
COM
NO/NC
!"
#$
%
&
&
&
' ( %
)*"!!+,-#
./
.&
0)/1.!
'"1!./
'"1!./)
./
2)
&.3
(
!.*
0).!!
IMPORTANT
è
Thermostat
Stage
Thermostat
Output
Heat
Pump
Stage
% of
Selected
CFM
Heat Call
Status on
Digital Display*
Discharge Air
Temperature
Target
1
Y1/G
1
50% or 70%**
HC1
L048
2
Y1/Y2/G
2
100%
HC1
L048
3
Aux/Y1/Y2/G
2
100%
HC2
L049
Fan
G
0
400 cfm
HCF
N/A
Cool 1
Y1/G/O
1
50% or 70%**
COOL
N/A
Cool 2
Y1/Y2/G/O
2
100%
COOL
N/A
Emergency
H/E
0
100%
HC3
L049
Contractor Use Only
TWO STAGE HEAT PUMP
*
If multiple inputs are active, system
will display highest Heat Call values.
** Systems built before 1/1/2011 are
configured for 50% airflow in Stage 1.
For more information, refer to
Instruction #1200601-High Speed
Stage 1 Relay Installation.