
Page 6 of 8 / IOM 1177-1 / LIAF184
Sensor Functions
Figure 4: Sensor switches and functions
Status LED
Occupancy Switch
Override Reset
Button
System Switch
Fan Switch
Room Temperature
Adjustment
This sensor is used for water source heat pump
applications requiring the following functionality:
•
Cool/Warm Room Temperature Adjustment
–
This slide adjustment is used to set the desired room
temperature. To increase the desired room temperature,
move the slide to the right toward “Warm”. To decrease
the desired room temperature, move the slide to the left
toward “Cool”.
•
Occupancy Switch
– Move the switch to the “Occ” to
allow the unit to operate in the occupied mode. Move
the switch to the “Unoc” to allow the unit to operate in
the unoccupied mode. Move the switch to the “Off” so
heating, cooling and the fan remain off.
•
System Switch
– Set to “Heat” for heating only operation.
Set to “Auto” for operation of heating or cooling as
needed to satisfy the room setpoint conditions. Set to
“Cool” for cooling only operation. The output voltage
on Terminal 2 will change based on the system mode
selection.
•
Fan Switch
– Set to “Auto” to allow the fan to cycle with
all requests for heating or cooling capacity. Set to “On”
to allow the fan to operate continuously as long as the
MicroTech III control is not in an alarm condition.
•
Status LED
– This green LED will light to indicate the
system status. See
Table 8
for unit status LED definitions.
•
Override Button
– When the “Override” button is
pressed, the thermistor sensor across terminal 4 is shorted.
If held for more than 5 seconds but less than 11 seconds,
it puts the water source heat pump controller into a timed
Occupied Override. If the unit is in alarm, then holding
the “Override” Button for more than 11 seconds will clear
all alarms in the water source heat pump controller but
only if the cause of the alarm has already returned to its
non-alarm condition. Some alarms will not reset from the
room sensor.
In this case, power to the unit must be cycled off for 5 sec
-
onds to clear the alarm. Continuously resetting alarms from
the room sensor could damage the controller. Please call a
service technician when repeated alarm resets are required to
keep the unit operational.
Table 8: WSHP unit status LED definition
Status LED
Unit Status
Unit Operation
ON
OFF
0.5 seconds
0.5 seconds
Controller Off
(or Network “Wink”
operation active)
“Alarm”
0.0 seconds
Continuous
Unit running in Night
Setback Override
Mode or no power to
the sensor
“Override”
0.5 seconds
5.5 seconds
Unoccupied Mode
“Unoccupied”
5.5 seconds
0.5 seconds
Standby Mode
“Energy Save” or
“Load Shed” com
-
mand from Energy
Management System
Continuous
0.0 seconds
Occupied Mode
“Occupied”