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IM 938-4 / Page 18 of 42
2) Hot Keep
In Hydronic Heat:
When the water valve closes, the
indoor fan will operate per the user mode (Constant or
Cycle) and speed setting.
Heat Fan Lock Out Control:
When the unit is in the Heat
Mode, but when hot water or steam is not available, it pre
-
vents the indoor fan from operating. The indoor fan will only
operate in the “Fan Only” and “Cool Modes”.
In Electric Heat:
When the heater cuts out the indoor fan
will continue to run for 15 seconds at set speed regardless of
“On or Off” mode.
3) Sleep Function
Sleep time is user adjustable from 1 to 15 hours in one
hour increments in a closed loop via the touch pad by
pressing the Sleep button repeatedly. The
Sleep Mode
can be terminated by pressing the On/Off button.
The Sleep Function will lower the temperature setting with
time. Changing the Mode or a changeover from Heat to Cool
will reset the Sleep Timer.
The Sleep function will be deactivated by Power-on-reset or
by pressing any button on the Touchpad except Sleep.
4) Fan Mode
In the Fan Mode, the fan will operate continuously
at the user’s speed setting. The compressor and
outdoor fan will not operate. In single motor units,
the outdoor fan will run along with the indoor fan.
Standard or Programmable Digital
Touchpad (LUI) Control Set-Up – Mode
Selection
To enter the Set Up Mode, simultaneously press the Up and
Down buttons for 5 seconds. To change settings, press the
Up or Down button. To move from one screen to another,
press the Mode button.
To exit Set Up, press the Up and Down buttons simultane
-
ously for 5 seconds or control will automatically exit Set Up
in 15 seconds.
Settings within the Set Up Mode are as follows:
1) Temperature Scale Selection
Once in the Set Up Mode, the temperature scale will be
displayed. To change the temperature scale to degree
Celsius, press the Up or Down button. The default setting
is "F", degrees Fahrenheit.
2) Temperature Limit Selection
To advance from Temperature Scale Selection to
Temperature Limit Settings, press the Mode button once.
To set the Cool Minimum set point, press and hold Fan
Cycle button, and adjust the setting with the Up or Down
buttons.
The minimum setting is 60°F.
3) To advance from Cool Minimum Set Point
to the Heat
Maximum set point, press the Mode button once.
To set the Heat Maximum set point, press and hold Fan
Speed button and adjust the setting with the Up or Down
buttons.
Maximum setting is 85°F.
Figure 28: If 0°F < Ts - Ts < 2°F, operation will be in
Zone C
Compressor
L
ow Fan
t
On
Off
On
Off
30 secs
.
30 secs
.
6 mins
.
6 mins
.
t
*
= Zone Determination Time
*
Figure 29: If Ts - Tr > 5°F, operation will be in Zone D
Compressor
Fan
t
On
Off
On
Off
t
12 mins
.
*
*
= Zone Determination Time
The other temperature ranges are dead bands for zone
stability.
Heat Mode
Unit will call for heating based on the type of the heat source
it has: heat pump in reverse cycle, hydronic or electric.
1) Hot Start
Hot Start is possible when the control has not called for
heat in more than (2) hours or during power-on-reset.
During Hot Start, the user’s set point is raised 4°F (Ts +
4°F). The unit will only call for heat if room temperature
differential calls for heat.
The unit will continue in Hot Start Mode until the new
set point is satisfied (with a 1°F differential) or unit has
run for at least 20 minutes. After one or both conditions
are met, the set point will be reset to the user’s setting
and the unit will run in regular heat mode. Hot start is not
available with the Sleep
feature.
The fan will operate per
the Fan Mode and Speed setting.