9
Under normal circumstances it is not necessary or advisable
to change these from their default values.
Heat Off Delay
If the system includes a G6 gas furnace, you may use the
or
keys to select HEAT OFF DELAY. Press the key to
enter the screen which allows changes to the length of time
that the blower (indoor fan) will remain on after the furnace
fl ame is extinguished. Under normal circumstances it is not
necessary or advisable to change this from its default value
of 120 seconds.
Altitude Adjust
If the system includes an iQ modulating gas furnace, you
may use the or keys to select ALTITUDE ADJUST.
Press the key to enter the screen which allows changes to
the installation altitude (feet above sea level). This entry is
advisable for the modulating gas furnace. Refer also to the
furnace Installation Instructions.
Service Tests
You may use the or keys to select SERVICE TESTS.
Press the key to enter the screen which allows access to
a list of service tests. These tests provide an easy way for
the service person to operate the system in various modes
for operational confi rmation and diagnostic troubleshooting
during installation startup. The following fi ve options are
available in the submenu.
S E R V I C E T E S T S
C H A R G E M O D E
A I R C O N D R U N T E S T S
F U R N A C E T E S T S
H E AT P U M P R U N T E S T S
D I S C R E T E O U T P U T S
NOTE: While running the system from Service Tests is
convenient for some startup operations, much of the normal
fault handling and diagnostic message functionality is disabled.
Within each test screen there may be more than one entry which
can be changed. Select the desired entry to be modifi ed using
the and keys. The line or value with a dark background
behind the characters is considered “selected”. Press the
key to allow changing the selected item (its dark background
will then blink). Set the desired value for the item using the
and keys, then press the key to save it.
The following is a brief description of the SERVICE TEST
categories. NOTE: With iQ Zone systems there may be a delay
before the test begins, as all zone dampers open.
CHARGE MODE – Runs the system at the proper speed for
checking and adjusting refrigerant charge. Select the mode as
HEATING or COOLING, then change RUN from OFF to ON.
The screen backlight will blink red. The user may navigate
to other screens (e.g., SERVICE INFORMATION) during the
process until ON in the CHARGE MODE screen is changed
back to OFF and saved. The red blinking backlight serves as
a reminder that the unit is operating in an abnormal (service)
mode. Select OFF (from the list that includes ON and OFF)
and SAVE ( ) when fi nished.
FURNACE TESTS – Runs the system at the selected fi re
level to allow confi rmation of proper operation. The screen
backlight will blink red. A short list of instructions (reminders)
is provided. Select START to run a single stage furnace. Select
LO FIRE or HI FIRE to run a two stage furnace. The user may
navigate to other screens (e.g., SERVICE INFORMATION)
during the process. The red blinking backlight serves as a
reminder that the unit is operating in an abnormal (service)
mode. Select DONE (from the list that includes LO FIRE, HI
FIRE, START, STOP) and SAVE ( ) when the test is complete,
before leaving the screen for the last time.
AIR COND RUN TESTS and HEAT PUMP RUN TESTS – In
these screens the unit can be made to run at a fi xed speed
regardless of room temperature. RUN can be changed
between OFF, MAX (speed), INTERMED(iate speed), and
MIN (speed). MAX speed is the same as that used in charge
mode. The screen backlight will blink red when anything but
OFF is selected and saved. The user may navigate to other
screens (e.g., SERVICE INFORMATION) during the process
until RUN in this screen is changed back to OFF and saved.
The red blinking backlight serves as a reminder that the unit
is operating in an abnormal (service) mode. This screen is
primarily intended for test agency usage. Heat pump run
tests apply only to heat pump units. Select OFF and SAVE
( ) when fi nished.
For iQ heat pumps the capability to force a defrost is available.
As indicated on the HEAT PUMP RUN TESTS screen, this
feature may only be used when MAX speed has been selected.
To perform a sample defrost while a MAX speed heating run
test is running, press the key to select DEFROST NOW, then
press the ( ) key to begin the defrost. The defrost sequence
will proceed, including use of auxiliary heat while heating the
coil and the 8 minute post-defrost coil temperature calibration.
Only use this feature if the outdoor conditions are typical
heating conditions. Do not force a defrost before the system
has operated in heating for several minutes fi rst.
DISCRETE OUTPUTS – When the unit is off, this screen
allows the user to operate certain relay-driven outputs in the
system for diagnostic purposes: humidifi er (on the indoor
interface board or blower control board), reversing valve (on
the outdoor interface board), indoor coil EXV (on the indoor
interface board or blower control board), outdoor coil EXV (on
the outdoor interface board), and crankcase heater (on the
outdoor interface board). More than one of these can be set
to ON at the same time. Leaving the DISCRETE OUTPUTS
screen will shut all of the listed outputs off.