Daikin MicroTech Operation And Maintenance page 58

Hydronic Water Coil Freeze Stat
Name: WaterCoilFreezeProblemAlarm
Description: Unit is configured to have a Hydronic Water
Coil Freeze Stat installed, the associated binary input is
open, and the face and bypass damper is enabled. Note: see
WaterCoilFreezeFaultAlarm for fault that occurs when the face
and bypass damper is disabled
Type: Problem
Activate: Unit is configured to have a Hydronic Water Coil
Freeze Stat installed and the associated binary input is open.
Upon active:
• Alarm is indicated on the LUI
• Fault relay is energized if alarm output configuration is
FAULTPROB.
• LED output alarm indication is activated
• OAD closes immediately
• Heating EOC Valve opens immediately
• Cooling EOC Valve opens immediately
• The face and bypass damper is 100% bypass for cooling
or temp OK. (2 position heating valve, 2 position heating
and cooling valve)
• The face and bypass damper is 100% bypass for heat
required or temp OK. (2 position cooling valve with no
electric heat)
• The face and bypass damper is 100% face if heating is
required. (2 position cooling valve with electric heat)
• The face and bypass damper is allowed to modulate if
heating is required. (2 position heating valve, 2 position
heating and cooling valve)
• The face and bypass damper is allowed to modulate if
cooling is required. (2 position cooling valve)
• The space fan is allowed to run. (All 2 position valves)
• The hot/cold water valves are forced to a minimum
position of 50%. If heating or cooling is required, the
valve is allowed to modulate above 50%
Deactivate: Hydronic Water Coil Freeze Stat binary input is
closed.
Reset: Auto
OM 1280-2 • MICROTECH UNIT CONTROLLER
Low Suction Line Temperature
Name: LowSuctionLineTempAlarm
Description: The suction line temperature is below the Low
Suction Line Temperature setpoint.
Type: Problem
Activate: If the unit is configured to have an indoor air coil/
suction line refrigerant temperature sensor and the reading is
reading <= Low Suction Line Temperature setpoint and the unit
is not in the defrost state.
Upon active:
• Alarm is indicated on the LUI
• Fault relay is energized if alarm output configuration is
FAULTPROB
• LED output alarm indication is activated
Deactivate: Indoor air coil/suction line refrigerant temperature
>= Low Suction Line Temperature setpoint + Low Suction Line
Temperature Differential.
Reset: 2 automatic resets in 7 days then a manual clear from
the LUI keypad, network or room sensor is required.
Can't Cool Failure
Name: CantCoolAlarm
Description: The unit is trying to cool, but conditions do not
allow this (entering water temperature is too high for hydronic
cooling), or no flow to the compressor for WSHPs.
Type: Problem
Activate: All of the following are true:
• Cooling is required
• Compressor cooling is unavailable.
• Entering water temperature is too warm for hydronic
heating
• Economizer cooling is unavailable
Upon active:
• Alarm is indicated on the LUI
• Fault relay is energized if alarm output configuration is
FAULTPROB
• LED output alarm indication is activated
Deactivate: Compressor or economizer cooling becomes
available, or the entering water temperature becomes cold
enough to provide cooling.
Reset: Auto
58
Diagnostics and Service
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