Microtech Iii Unit Controller Led Faults - Daikin Enfinity VFC Installation And Maintenance Manual

MicroTech III Unit Controller LED Faults

Table 14: 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 15: 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 16: Compressor Low Pressure
Description*
Compressor Low Pressure
• Loose wire connection on low pressure circuit
• Failed low pressure switch
• Unit is low on charge
Table 17: 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 18: Condensate Overflow
Description*
Condensate Overflow
• Poor condensate drain
• Check the resistance to ground on condensate wire. This should be open if there is no water in the pan.
Table 19: Serial EEPROM Corrupted
Description*
Serial EEPROM Corrupted
• Cycle power to see if problem is corrected.
• Replace main board, only if problem persists after power cycle.
Table 20: Service Test Mode Enabled
Description*
Service Test Mode Enabled
• Jumper JP1 is shorted for service test mode operation. Note: Used only for testing purposes, control timing may damage actual hardware.
Table 21: Unoccupied Mode
Description*
Unoccupied Mode
• Terminal U on main control board is connected to common from external source, or the network is overriding occupancy mode.
IM 930-6 • Enfinity Vertical Water Source Heat Pumps
Type Yellow
Fault OFF
Mode OFF
Type Yellow
Fault OFF
Type Yellow
Fault OFF
Type Yellow
Fault Flash
Type Yellow
Fault ON
Type Yellow
Fault ON
Type Yellow
Mode Flash
Type Yellow
Mode ON
34
t
roubleshooting
Green Red
Flash OFF
Flash OFF
Green Red
OFF Flash
Green Red
OFF ON
Green Red
Flash ON
Green Red
OFF OFF
Green Red
ON ON
Green Red
Flash Flash
Green Red
ON OFF
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