IM 934-2 Applied PDAA/PDHA / Page 24 of 44
Figure 35. Indoor Air and Indoor Coil Sensor
Locations
Indoor
Coil Sensor (ICS)
Indoor
Air Sensor (IAS)
Heat Mode
Unit will call for heating based on the type of
the heat source it has: heat pump in reverse cycle 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.
2) Hot Keep:
When the water valve closes, the indoor fan will
operate per the user mode (Constant or Cycle) and
speed setting.
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.
Set Up Mode
To enter the Set Up Mode, simultaneously press the
Mode, 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 Mode Up and Down
buttons simultaneously for 5 seconds or control will
automatically exit Set Up in 15 seconds.
Settings within the Set Up Mode are as follows:
Control Selection:
To view the Control Selection Screen, press and
hold the Up and Down buttons for 5 seconds. The
setting may be changed by pressing either the Up or
Down button. The “tP” setting is the default setting
and indicates the touchpad control.
Temperature Limit Settings
To advance from Control 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.
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.
The Display will show the upper operating limits
first. The default settings are Cool min. = 60°F and
Heat max. = 85°F.
Hydronic Valve Operation
To advance from Temperature Limit Settings to
Hydronic Valve operation, press the Mode button
once. To toggle the setting, press either the Up or
Down button. Settings are “no” (normally open) and
“nc” (normally closed). Default setting is “no”.
Indoor Air Sensor Reading
To advance from Hydronic Valve operation to
Indoor Air Sensor Reading, press the Mode Button
once. The control readout will show room temperature.
Modes of Operation-Description
Standard Digital Touchpad Control
6.3
Heat mode
Unit will call for heating based on the type of the heat source it has: heat pump in reverse cycle or electric.
6.3.2
Hot Start
6.3.2.1 Hot start is considered when the control hasn’t called for heat for more than 2
hours or during power-on-reset.
6.3.2.2 During Hot start in heat mode user’s set point is raised 4°F (Ts+4°F). Unit will
call for heating if temperature differential is asking for it.
6.3.2.3 Unit will Hot start until set point is satisfied (with 1 degree differential) or unit
has run in Hot start for at least 20 minutes. After one or both conditions are
met, user’s set point will be reset to the original setting and unit will run in
regular heat mode
6.3.2.4 Hot start is not available with
Sleep
feature
6.3.3 Control will call for the type of heat that the unit has (example: heat pump or electric heat)
6.3.3.1 For
HP
selection compressor cut in and out conditions are:
a) Heat cut-in shall occur when Tr-Ts<-2°F
b) Heat cut-out shall occur when Tr-Ts>3°F
6.3.3.1.1 Hot Start: the indoor fan operation is determined according to the
indoor coil temperature:
a) Fan will stop if indoor coil temp falls below 59°F
b) Fan will run at users set speed when indoor coil temp
rises back to 61°F
6.3.3.1.2 Hot Keep: when compressor cuts out or not running, the indoor fan
will run according to indoor coil temperature
a) Fan will stop if temp drops below 59°F
b) Fan will run at user’s speed if temp rises back to 61°F
6.3.3.1.3 Reversing valve output is turned on in heat mode. It turns off 5
seconds after the compressor has turned off.
6.3.3.1.4 Defrosting of the outdoor coil will be activated when outdoor coil
temp drops below 20°F or outdoor air temperature drops to 35°F
or less. Defrosting is terminated when outdoor coil temp rises
back to 40°F. During defrosting both compressor and the outdoor
fan are turned off. The indoor fan will run at user’s set speed.
6.3.3.2 For
AC/E
selection, the heater cut in and out conditions are:
a) Heat cut-in shall occur when Tr-Ts<0°F
b) Heat cut-out shall occur when Tr-Ts>3°F
6.3.3.2.1 When the heater cuts out the indoor fan continues to run for 15 sec at
set speed, regardless of On or Off mode. After 15 seconds the fan
will stop running if unit is in Off mode, else the fan operation will
depend on Fan Continuous or Cycle setting.
PRELIMINARY
