Accessories; Electronic Air Cleaner; Humidification And Dehumidification - Rheem RGFG Installation Instructions Manual

ACCESSORIES

FIELD-INSTALLED
OPTION ACCESSORIES
TWINNING: Twinning is NOT permitted
on any modulating furnace model.

ELECTRONIC AIR CLEANER

Line voltage power is supplied from the
terminal "EAC", see Figure 30, and a
neutral terminal on the control board.
This will power the electronic air cleaner
whenever the blower is operating and
delivering the recommended minimum
CFM. The 60 and 75 KBTU models,
which are capable of a maximum deliv-
ery of 1200 CFM, will operate the elec-
tronic air cleaner at 500 CFM and
above. The 90, 105 and 120 KBTU mod-
els, which are capable of a maximum
delivery of 2000 CFM, will operate the
electronic air cleaner at 800 CFM and
above. These limits are set to prevent
excessive production of ozone at the
lower airflows of the modulating furnace
and are based on average requirements
of commercially available electronic air
cleaners.
Continuous fan speeds are selectable
and some lower fan speeds may not
deliver enough airflow to operate an
electronic air cleaner. The IFC deter-
mines the minimum airflow necessary to
operate an electronic air cleaner and will
not turn on the electronic air cleaner
unless the airflow is high enough for the
EAC.
The electronic air cleaner will not be
energized until 20-30 seconds after the
main blower has been energized.
HUMIDIFICATION AND DEHUMIDIFI-
CATION
Note: The humidifier output will be
energized briefly during a heat call
while the igniter is on (igniter warm-up
period) even when there is no demand
for humidification.
HUMIDIFIER – The humidifier contacts
(labeled "HUM OUT") are "dry" contacts
FIGURE 30
EAC AND HUMIDIFIER TERMINALS ON FUR-
NACE CONTROL (IFC)
on the I.F.C. This means that the termi-
nals are connected directly to the con-
tacts of a board-mounted relay. The coil
of the relay is controlled by the micro-
processor of the IFC. The coil is
engaged roughly any time the heat
speed blower is engaged and (1)
24VAC is present on the thermostat ter-
minal of the IFC labeled "HUM STAT" or
(2) a communicating thermostat with

humidification and dehumidification

capability is installed with call for
humidification present.
An optional 24VAC humidistat can be
installed as shown in Figures 31 thru 34
FIGURE 31
WIRING FOR OPTIONAL HUMIDIFICATION (AND DEHUMIDIFICATION WITH COMMUNICATING
THERMOSTAT) WITH OPTIONAL HUMIDIFIER AND NO HUMIDISTAT (HUMIDIFICATION ACTIVE
DURING ANY HEAT CALL) (FOR USE WITH COMMUNICATING AND NON-COMMUNICATING
THERMOSTATS)
FIGURE 32
WIRING FOR OPTIONAL DEHUMIDIFICATION WITH HUMIDIFICATION (WITH OPTIONAL
HUMIDISTAT AND HUMIDIFIER)
NOTE: CAN BE USED WITH COMMUNICATING OR
NON-COMMUNICATING SYSTEMS
(II thru IV). With the optional
humidistat, two separate co nditions
must be met before humidification
can begin 1). There must be a call
for heat and the blower must be
engaged and 2.) The humidistat
must determine that there is a need
for humidification.
Note: Dipswitch S5-1 enables
("ON") or disables ("OFF") dehumidi-
fication operation. However, it has
no affect on humidification opera-
tion. If this switch is set to the "ON"
position and no humidistat is
installed, the cooling airflow will be
37