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alert will show you one of the below alerts. All these alerts are
generated by the OAU device and reported to the MBB. These
alerts can only occur if the Outdoor Air Unit Type (
Configura-
tion
OAU
OA.TY
) is not set to 0. Control action is only tak-
en on the OAU side and these alerts will reset automatically
when the OAU clears them. Refer to the EnergyX Supplemental
Installation Instructions for more information on these alarms.
• OAU Motor Failure
This alert occurs when the OAU Motor Failure Alarm (
Operat-
ing Modes
OAU
ALM.1
) is on. This is usually due to mo-
tor status reporting a failure on the OAU.
• OAU Dirty Filter
This alert occurs when the OAU Dirty Filter Alarm (
Operating
Modes
OAU
ALM.2
) is on. This is usually due to filter sta-
tus reporting a dirty filter on the OAU.
• OAU Low CFM
This alert occurs when the OAU Low CFM Alarm (
Operating
Modes
OAU
ALM.3
) is on. This is usually due to OAU not
capable of achieving proper CFM. If unit is equipped with a
VFD on the indoor fan, the configuration OAU Fan Boost En-
able is set to yes (
Configuration
OAU
EFBE = Yes
), and
this alarm is active for 10 minutes, the fan will be commanded
to the next highest configured fan speed. If this alarm is still
active after another 10 minutes, the fan will again change to the
next highest configured fan speed, and so on every 10 minutes
until the maximum speed is commanded. The fan will stay at
this override commanded speed until this alarm clears and a
different function changes the commanded speed.
• OAU General Alarm
This alert occurs when the OAU Alarm (
Operating Modes
OAU
ALM.4
) is on. Refer to the specific OAU documen-
tation for details.
Alert Code A420 — Supply VFD Fault
This alarm occurs when the VFD has faulted and communi-
cates it to the Main Base Board (MBB). The last VFD fault
number can be viewed as VFD1 Last Full code (
Run Sta-
tus
S.VFD
LFC
). Refer to VFD major component section
for details on its alarms and faults. The alarm will shut down
the unit if the fan ramps down to 0%. This alarm will automat-
ically reset or can be reset through the display.
Table 14 —
Comfort
Link Alarm Codes
ALARM
OR
ALERT
NUMBER
DESCRIPTION
ACTION TAKEN BY
CONTROL
RESET
METHOD
PROBABLE CAUSE
T051
Compressor A1 Safety Trip
Add Strike for Circuit A
Automatic High-pressure switch open. Compressor internal
protection open. Wiring error
Service Test — Compressor A1
Safety Trip
Compressor A1 Detected After
Turnoff
Turn off all compressors
Automatic Welded contactor
Service Test — Compressor A1
Detected After Turnoff
T055
Compressor B1 Safety Trip
Add Strike for Circuit B
Automatic High-pressure switch open. Compressor internal
protection open. Wiring error
Service Test — Compressor B1
Safety Trip
Compressor B1 Detect After Turnoff Turn off all compressors
Automatic
Welded contactor
Service Test — Compressor B1
Detected After Turnoff
T064
Circuit A Saturated Condensing
Temp Thermistor Failure
Limited Diagnostic
Automatic Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
T065
Circuit B Saturated Condensing
Temp Thermistor Failure
Limited Diagnostic
Automatic Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
T066
Circuit A Saturated Suction
Temperature Thermistor Failure
No Circuit A Cooling
Automatic Circuit A Suction transducer internally forced inactive
T067
Circuit B Saturated Suction
Temperature Thermistor Failure
No Circuit B Cooling
Automatic Circuit B Suction transducer internally forced inactive
T073
Outdoor Air Temperature
Thermistor Failure
No cooling with economizer
Automatic Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
T074
Space Temperature Thermistor
Failure
If U.CTL = 3, then no heating
or cooling
Automatic Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
T075
Supply Air Temperature Thermistor
Failure
No cooling with economizer
and No adaptive compressor
staging
Automatic Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
T076
Return Air Thermistor Failure
If RAT.S = Yes, then no
differential Dry Bulb control
Automatic Faulty, shorted, or open thermistor caused by wiring
error or loose connection.
T077
Space Relative Humidity Sensor
Failure
If RH.S = Yes, then no indoor
humidity control
Automatic Faulty, shorted, or open sensor caused by wiring error
or loose connection.
T092
Circuit A Suction Pressure
Transducer Failure
Lockout Circuit A
Manual Faulty transducer, faulty 5-V power supply, or loose
connection
T093
Circuit B Suction Pressure
Transducer Failure
Lockout Circuit B
Manual
Faulty transducer, faulty 5-V power supply, or loose
connection
T102
Compressor A1 Current Sensor
Failure
If CS.A1 = Enable, then no
T051 current alarm
Automatic Faulty transducer, faulty 5-V power supply, or loose
connection
T103
Compressor A1 Current Sensor
Failure
If CS.B1 = Enable, then no
T055 current alarm
Automatic Faulty transducer, faulty 5-V power supply, or loose
connection
T110
Circuit A Loss of Charge
Lockout Circuit A
Manual
Low refrigerant or faulty suction pressure transducer
Service Test — Circuit A Loss of
Charge
Summary of Contents for /50HC 04-28
Page 69: ...69 Fig 24 Typical Control Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 70: ...70 Fig 25 Typical Power Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 71: ...71 Fig 26 Typical Control Diagram for 50HC 04 14 Units 50HC 14 shown ...
Page 72: ...72 Fig 27 Typical Power Diagram for 50HC 04 14 Units 50HC 14 Non Humidi MiZer shown ...
Page 73: ...73 Fig 28 Typical Control Diagram 48HC 17 28 Units ...
Page 74: ...74 Fig 29 Typical Control Diagram 50HC 17 28 Units ...
Page 75: ...75 Fig 30 Typical Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 76: ...76 Fig 31 Typical Non Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 89: ...89 Fig 42 Modulating ERV Wiring Schematic ...
Page 90: ...90 Fig 43 EnergyX ERV Control Box Component Layouts ...
Page 101: ...101 Fig 59 Exhaust Fan Assembly Removal Exhaust Fan Assembly ...
Page 141: ......