Troubleshooting; Microtech Iii Unit Controller Led Faults - Daikin Enfinity CCW Installation And Maintenance Manual

MicroTech III Unit Controller LED Faults

Table 11: Low Voltage Brownout or Emergency Shutdown
Description
Low Voltage Brownout
Emergency Shutdown
* Same LED display for both conditions
• Verify the E terminal is not connected to common. Remove wire, if connected, and LED should change to solid green only
• Confirm the low voltage supply is between 19-32VAC at the H1 terminal of the main board. If the low voltage supply is out of range, verify the unit
supply voltage matches the nameplate voltage and the correct transformer primary wire has been selected
Table 12: Compressor High Pressure
Description
Compressor High Pressure
• Verify high pressure switch is connected to terminal H3 on the main board
• Check for continuity of the high pressure switch
If the high pressure fault resets when power is cycled
• Check water flow (cooling operation)
• Check airflow (heating operation)
• Entering water and air temperatures should be within the operating limits
Table 13: Compressor Low Pressure
Description
Compressor Low Pressure
• Loose wire connection on low pressure circuit
• Failed low pressure switch
• Unit is low on charge
Table 14: Compressor Suction Temp Fail, Room Temp Sensor Fail, Leaving Water Temp Sensor Fail
Description
Compressor Suction Temp Sensor Fail
Room Temp Sensor Fail (Room Sensor Control Only)
Leaving Water Temp Sensor Fail
• Check connection of low suction temperature sensor on terminal H6 pins 2 and 3
• Check resistance of low suction temperature sensor, leaving water temperature sensor, and room sensor or return air sensor. All sensors are
10kohm thermistor @77°F
• Return air sensor and room sensor shall not be connected simultaneously
Table 15: Compressor Low Suction Temp
Description
Compressor Low Suction Temp
• Check water flow (heating operation)
• Check airflow (cooling operation)
• Entering water and air temperatures should be within the operating limits
Table 16: Low Entering Water Temp
Description
Low Entering Water Temp
(No Display with Boilerless EH)
• Low entering water temperature (below 35°F standard range or 13.5°F extended range)
Table 17: Condensate Overflow
Description
Condensate Overflow (Cooling &
Dehumidification Modes Only)
• Poor condensate drain
• Check the resistance to ground on condensate wire. This should be open if there is no water in the pan
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Type Yellow
Fault OFF
Mode OFF
Type Yellow
Fault OFF
Type Yellow
Fault OFF
Type
Fault
Fault
Fault
Type Yellow
Fault Flash
Type Yellow
Fault Flash
Type Yellow
Fault ON
37
Green
Flash
Flash
Green
OFF
Green
OFF
Yellow Green
Flash Flash
Flash Flash
Flash Flash
Green
OFF
Green
OFF
Green
OFF
t
roubleshooting
Red
OFF
OFF
Red
Flash
Red
ON
Red
ON
ON
ON
Red
OFF
Red
Flash
Red
OFF
IM 1049-9