SYSTEM OPERATION
32
Fossil Fuel Applications
This furnace can be used in conjunction with a heat pump in a
fossil fuel application. A fossil fuel application refers to a combined
gas furnace and heat pump installation which uses an outdoor
temperature sensor to determine when to run the heat pump
or gas furnace.
For non-communicating single stage heat pump installations a
fossil fuel kit can be used. Follow the wiring guidelines in the
fossil fuel kit installation instructions. All furnace connections
must be made to the furnace integrated control module and
the “FURNACE” terminal strip on the fossil fuel control board.
For Fossil Fuel systems the heat pump is given priority
when a compressor balance point lockout condition is
not present. Transitions from primary heat pump heat
-
ing to backup gas heating will result in full capacity
operation during the first thermostat call. The furnace
PCB algorithms will then continuously adjust the stage
times or the percent capacity after the initial call in an
attempt to satisfy the thermostat at the target runtime.
Automatic Fossil Fuel Adjustment: If both compressor
balance point and backup heat balance point lockouts
are not present, the furnace algorithms will determine
if the heat pump is capable of satisfying the thermostat
in the selected target runtime. If the heat pump is not
capable of this it will be locked out until the furnace
can satisfy the thermostat, under the target runtime,
while running completely in low stage. At that point,
an attempt will be given to the heat pump and a deci
-
sion made to keep using gas heat or to transition back
to the heat pump.
115 Volt Line Connection of Electronic Air
Cleaner
HIGH VOLTAGE !
T
O
AVOID
PERSONAL
INJURY
OR
DEATH
DUE
TO
ELECTRICAL
SHOCK
,
DISCONNECT
ELECTRICAL
POWER
BEFORE
SERVICING
OR
CHANGING
ANY
ELECTRICAL
WIRING
.
WARNING
The accessory load specifications are as follows:
EAC
1.0 Amp maximum at 120 VAC
The furnace integrated control module is equipped with a
line voltage accessory terminal for controlling power to an
optional field supplied electronic air cleaner or any device
required to operate in parallel with a circulating fan
demand.
To connect an electronic air cleaner using the line volt
-
age EAC terminal:
•
Turn OFF power to the furnace before installing any
accessories.
•
Follow the air cleaner manufacturers’ instructions
for locating, mounting, grounding, and controlling
accessories. Utilize 1/4” quick connect terminals to
make accessory wiring connections to the furnace
integrated control module.
•
Connect the hot terminal utilized for accessory operation
to the EAC terminal and the neutral side of power to
NEUTRAL bus on the integrated furnace control or the
neutral connection in the furnace junction box.
•
All field wiring must conform to applicable codes.
•
Connections should be made as shown.
•
If it is necessary for the installer to supply additional line
voltage wiring to the inside of the furnace, the wiring
must conform to all local codes, and have a minimum
temperature rating of 105°C.
•
All line voltage wire splices must be made inside the
furnace junction box.
Auxiliary Alarm Switch:
The control is equipped with a 24VAC Aux Alarm to be
used for a condensate switch install (designated by
“Condensate” on the control).
These contacts could
also be used with compatible CO
2
sensors or Fire Alarms.
By default, an AUX switch is normally closed and opens
when the water level in the evaporator coil base pan
reaches an undesirable level. The control will respond
by turning off the outdoor condensing unit and display
EEd. If the AUX switch is detected closed for 30 seconds,
normal operation resumes and error messages are no
longer displayed.
CoolCloudHVAC Phone Application – General Information
Examples of CoolCloudHVAC Phone Application
Screens
NOTE: Actual screen may look different based on the
device being used.