OM 931-6 • MicroTech III Unit Controller for WSHP
12
www.DaikinApplied.com
Fan Operation during
most Modes, Faults and
Shutdowns
The MicroTech III unit controller allows fan operation
during most modes, faults and shutdowns to facilitate
maximum space comfort and control. However, the fan
does not operate during emergency shutdown or brownout
condition. During most modes, faults, or shutdowns the fan
will operate under the following conditions:
1. In occupied modes, the thermostat inputs G, Y1, or
W1 are energized.
2. In unoccupied mode, the thermostat input W2 is
energized.
Operation with the High Speed Jumper
■ The MicroTech III unit controller includes a high-
speed jumper terminal labeled JP1 to speed system
check out and trouble-shooting. See Figure 2 on
page
6
for JP1 location.
Note: This jumper is intended for Daikin factory unit
testing and should only be used by trained ser-
vice technicians as several timing functions are
reduced to speed system check out.
■ Disconnect power to the unit when installing or
removing the high-speed jumper.
■ The high speed jumper should only be used for a
short period of time for testing of the unit’s operation
by a trained service technician. The jumper must be
removed for normal unit operation.
■ If the jumper is left on after system check out, the
unit may be damaged.
Priority of Faults and Modes
The MicroTech III unit controller is configured with mode
and fault priorities. Table 4 illustrates that the lower the
priority level number, the higher the priority of the fault or
mode. There are some exceptions to this priority list. For
example, tenant override has no affect on occupied modes.
Table 4: Priority Level of Faults and Modes
Priority Level
Mode or Fault
1
Emergency Shutdown Mode
2
Brownout
3
Compressor High Pressure
4
Compressor Low Pressure
5
Compressor Suction Temp Sensor Fail
6
Compressor Low Suction Temp
7
Room Temp Sensor Fail
8
EWT Sensor Fail
9
Condensate Overflow
10
Serial EEPROM Corrupted
11
Invalid Jumper Configuration
12
Low Entering Water Temp
13
Service Test Mode
14
Unoccupied Mode
15
Occupied, Bypass, Standby or Tenant Override
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Table 5: MicroTech III Unit Controller Status LED's
Description
Type
Yellow
Green
Red
Emergency Shutdown
Mode
OFF
Flash
OFF
Low Voltage Brownout
Fault
OFF
Flash
OFF
Compressor #1 High Pressure (HP1)
Fault
OFF
OFF
Flash
Compressor #1 Low Pressure (LP1)
Fault
OFF
OFF
ON
Compressor #1 Low Suction Temp (LT1) Sensor Fail
Fault
Flash
Flash
ON
Compressor #1 Low Suction Temp (LT1)
Fault
Flash
OFF
OFF
Room Temp Sensor Fail
(with Room Sensor Control Only)
Fault
Flash
Flash
ON
Condensate Overflow
(Cooling & Dehumidification Modes Only)
Fault
ON
OFF
OFF
Low Entering Water Temp
(Heating Compressor Inhibit; No Display with Boilerless EH)
Fault
Flash
OFF
Flash
Serial EEPROM Corrupted
Fault
ON
ON
ON
Service Test Mode Enabled
Mode
Flash
Flash
Flash
Unoccupied Mode
Mode
ON
ON
OFF
Occupied, Bypass, Standby, or Tenant Override Modes
Mode
OFF
ON
OFF
