Accessories - Goodman GRL SERIES Installation Instructions Manual

THERMOSTAT
NOTE: Do not use 24 volt control wiring
smaller than No. 18 AWG.
A single- or two-stage thermostat may
be used, however, a two-stage
thermostat is recommended for
optimum performance.
The room thermostat must be
compatible with the integrated furnace
control on the furnace. Generally, all
thermostats that are not of the "current
robbing" type are compatible with the
integrated furnace control being used.
Install the room thermostat in
accordance with the instruction sheet in
the box with the thermostat. Run the
thermostat lead wires inside the control
compartment. Connect the thermostat
as shown on the wiring diagram. Never
install the thermostat on an outside wall
or where it will be influenced by drafts,
concealed hot or cold water pipes,
lighting fixtures, radiation from fireplace,
rays of sun, lamps, television, radios or
air streams from registers. Refer to the
instructions packed with the thermostat
for best anticipator adjustment or
selection. Locate the thermostat
approximately five feet up from the floor.
HEAT ANTICIPATOR SETTINGS
If a current reading taken at the
thermostat is not performed, an initial
setting of .15 amps is recommended.
Adjust as needed to improve comfort
level.
ISOLATION RELAY
IMPORTANT: Not all electronic
thermostats are compatible with the
furnace control system. Some may
require an isolation relay.
If an isolation relay is required (part 42-
25104-01), install it as close to the
Integrated Furnace Control (IFC) as
possible. Use a single-pole, single-
throw relay with a 24-volt operating coil.
The relay contacts should be designed
for 24-volt loads.
Connect one end of the operating coil to
the thermostat "W" terminal. Connect
the other end of the coil to the "C"
terminal on the IFC. See Figure 30.
Connect one side of the normally open
contacts to the IFC "W" terminal.
When the thermostat calls for heat, it
powers the 24-volt operating coil. This
closes the relay contacts and conducts
power from terminal 3 and 4 to terminal
"W" on the IFC and starts the furnace
ignition sequence.
FIELD-INSTALLED OPTIONAL ACCESSORIES
ELECTRONIC AIR CLEANER
Electronic air cleaner line voltage power
can be supplied from the screw terminal
"EAC" and a line voltage neutral screw
terminal on the control board. This will
power the electronic air cleaner
whenever the circulating air blower is in
operation.
HUMIDIFIER
Line voltage power can be supplied
from screw terminal "HUM" to a line
voltage neutral screw terminal on the
control board. This will power the
humidifier during a normal heat
sequence after the blower has turned
on.
NOTE: Maximum current of 1.0 Amp
for each option.
FIGURE 30
ISOLATION RELAY
ST-A0804-01
33