Rheem RGFE, Installation Instructions Manual

Page: 47 / 132

HUMIDIFICATION AND DEHUMIDIFI-
CATION
HUMIDIFIER – The humidifier contacts
(labeled “HUM OUT”) are “dry” contacts
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
microprocessor 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.
ACCESSORIES
FIELD-INSTALLED
OPTION ACCESSORIES
TWINNING: Twinning is NOT permitted
on any modulating RGFE, RGGE or
RGJF furnace model.
ELECTRONIC AIR CLEANER
Line voltage power is supplied from the
screw terminal “EAC”, see Figure 53,
and a line voltage neutral screw 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 capa-
ble of a maximum delive ry of 1200 CFM,
will operate the electronic air cleaner at
500 CFM and above. The 90, 105 and
120 KBTU models, 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.
FIGURE 53
EAC AND HUMIDIFIER TERMINALS ON FUR-
NACE CONTROL (IFC)
FIGURE 54
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 55
WIRING FOR OPTIONAL DEHUMIDIFICATION WITH HUMIDIFICATION (WITH OPTIONAL
HUMIDISTAT AND HUMIDIFIER)
NOTE: CAN BE USED WITH COMMUNICATING OR
NON-COMMUNICATING SYSTEMS
An optional 24VAC humidistat can
be installed as shown in Figures 54
thru 54 (II thru IV). With the optional
humidistat, two separate conditions
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 SW2-1 (labeled
“ODD”) enables (“ON”) or disables
(“OFF”) dehumidification operation.
However, it has no affect on humidi-
fication operation. If this switch is
set to the “ON” position and no
humidistat is installed, the cooling
JUMPER SHOULD NOT BE INSTALLED
WHEN USING A COMMUNICATING
THERMOSTAT WITH HUMIDIFICATION
AND DEHUMIDIFICATION CAPABILI-
TIES.
FIELD INSTALLED JUMPER
FROM “R” TO “HUM STAT”
TERMINALS
NOTE:
DO NOT USE COMMUNICATING
THERMOSTAT MODEL
(-)HC-TST501CMMS IF HUMIDITY
CONTROL VIA THE THERMOSTAT
IS NEEDED
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