17
Five--Minute Compressor Timeguard
This timer prevents compressor from starting unless it has been off
for at least 5 minutes. It can be defeated by simultaneously pressing
the Fan and Temp + buttons.
Emergency Heat (for heat pump applications)
To activate Emergency Heat, you must press and hold the HEAT
button for 3 seconds to activate. Repeat to deactivate.
Heat Source Selection (Hybrid or Hydronic Heat)
If user wishes to override normal operation in Hybrid Heat or
Hydronic Heat applications, press and hold the heat button for 3
seconds to select desired heat source.
Keypad Lockout
Keypad can be locked by pressing “Fan” and “ZONE” buttons at
the same time for 3 seconds. When keys are locked, a lock symbol
will appear in the upper left corner of screen. Follow same
procedure to unlock keypad.
Heat and Cool LED
The Heat and Cool LEDs will pulsate during actual equipment
operation. This can be defeated in the Advanced Setup Screens.
Equipment Cycle Timer (adjustable 4--6 cycles per
hour)
This timer prevents the start of a heating or cooling cycle until 15
(or 10) minutes after the last start of the same cycle. Its function is
to assure that the equipment is not cycled more than the selected
times per hour. This timer is adjustable from 4 to 6 cycles per hour.
This timer is defeated for one cycle when the desired temperature is
manually changed. It can also be defeated for one cycle by
simultaneously pressing the Fan and Right Up buttons.
Staging Timer
In multistage heating or cooling, this timer prevents any higher
stage from turning on until the preceding stage has been on for 10
minutes.
In Hybrid Heat, the staging timer is 15 minutes between heat pump
and gas furnace operation. A demand of 5
_
F(3
_
C) or more will
override the staging timer and allow higher stages to energize.
Three--Minute Minimum On Time
In normal operation, when a stage turns on, it will remain on for a
minimum of three minutes. If the setpoint is changed, this timer is
automatically cancelled, allowing the equipment to turn off
immediately when the demand is removed.
Heat/Cool Setpoints (Desired Temperatures)
A minimum difference of 2
_
F (1
_
C) (default) is enforced between
heating and cooling desired temperatures. This is done by allowing
one setting to “push” the other to maintain this difference. This
difference is adjustable via the Install/Service menu under
Thermostat Setup.
Temperature Display
The actual temperature displayed is always rounded toward the
setpoint. This is because the system is operating and measuring the
temperature in sixteenths of a degree, but displaying in whole
numbers. The system may be turned off and on within .5
_
of
setpoint, but the display may not change. This is by design and
does not indicate a problem with the control.
Auto Changeover
When Auto mode is enabled (factory default) a change from heat
to cool (or vice versa) will not occur until an opposite mode
demand has existed for 30 minutes. If the setpoint is changed, the
30--minute requirement is defeated. This Auto Changeover time is
adjustable via the Install/Service menu under Thermostat Setup.
Range = 5 -- 120 min.
Smart Recovery
With Smart Recovery selected (factory default), transition out of
setback begins 1.5 hours before selected recovery time and
gradually adjusts room temperature so desired temperature will be
achieved at selected recovery time. It operates in both heating and
cooling. This only applies to programmable operation.
For example: Set back temperature in heating is 64
_
F. Smart
Recovery setpoint is 70
_
F at 7:00 a.m. At 5:30 a.m., the control
calculates the required temperature recovery rate (recovery temp --
set back temp or current temp if greater) / 90 minutes. If the current
temp at 5:30 = 66
_
F, the recovery rate = (70 -- 66)
_
F/90 minutes =
0.04
_
per minute. In order to achieve setpoint, the control ramps up
the setpoint 0.04
_
F / minute from 5:30 a.m. until 7:00 a.m. This
changing setpoint is displayed while it is occurring.
NOTE
: Temperatures should not be set back so far that the
equipment cannot recover in 90 minutes.
Air Filter
If
AIR FILTER
or
AIR PURIFIER
is installed in the indoor unit,
the system will perform a static pressure check of the system every
24 hours at 1:00 p.m. to monitor filter accumulation (TrueSense
t
Dirty Filter Detection) or whenever power is applied to the system
or the system is transitioned from Off to Cool or Heat modes. The
blower will run at a medium airflow for one minute.
This system operates by setting a base line static pressure based on
the highest airflow the system could run (this could be heat or cool
airflow). The measurement is taken at a low airflow and then
calculated up to the highest airflow the system could see.
Unoccupied
Pressing the HOLD button for 3 seconds will set the selected zone
to unoccupied status. A zone may also be programmed to be
unoccupied in any period of the schedule. An unoccupied zone is
used as a dump zone to alleviate high static or noise situations.
Utilizing this feature will help keep occupied zones at acceptable
temperatures and noise levels. The temperature in an unoccupied
zone is controlled to a maximum and minimum settings that are
selectable in the Advanced Setup. If the entire system is set to
Unoccupied, the humidity is controlled within the range selected in
the Unoccupied Advanced Setup. An unoccupied zone will be
allowed to be conditioned up to the most conditioned zone
setpoint, if necessary.
All Zones
Pressing the
ZONE
button for 3 seconds will gray out the entire
display and put the User Interface into “
ALL ZONES”
mode
(indicated by “All Zones” in upper left of the display). Any
changes to set temperature, fan, or Hold status will occur in all
zones when the screen is exited. Press the
ZONE
button to exit
“All Zones” mode. If no buttons are pressed for one minute, the
control will exit All Zones.
Frozen Coil Detection
During cooling operation, the User Interface will monitor the static
pressure of the system. If the static pressure is increasing
dramatically, the User Interface will turn off cooling for up to one
hour, record fault in the “Last 10 Events” screen, and run the fan at
a reduced airflow. The User Interface will continue to monitor the
static pressure. If it is reduced before one hour has elapsed, it will
resume cooling operation. After one hour, cooling will be resumed.
Airflow Limits and Equipment Protection
The maximum airflow allowed into a zone is based on the relative
size of the zone determined by the duct assessment and the airflow
limits selected for each zone. Airflow limits are set at High as
factory default. This means that 250% of assessed airflow is
allowed into the zone.
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