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48
T412
Thermostat W2 Input Activated
without W1 Activated
Run unit as if W2 and W1 are
On
Automatic Bad Thermostat or Thermostat Wiring
T413
Thermostat Y and W Inputs
Activated Simultaneously
Run unit in mode activated
first
Automatic Bad Thermostat or Thermostat Wiring
T414
Economizer Damper Actuator Out of
Calibration
Alert Generated
Automatic Calibrate economizer (
E.CAL
). If problem still exist then
determine what is limiting economizer rotation.
Economizer Damper Actuator
Torque Above Load Limit
Alert Generated
Automatic Actuator load too high. Check damper load.
Economizer Damper Actuator
Hunting Excessively
Alert Generated
Automatic Damper position changing too quickly.
Economizer Damper Stuck or
Jammed
Alert Generated
Automatic No economizer motion. Check damper blades, gears,
and actuator.
Economizer Damper Actuator
Mechanical Failure
Alert Generated
Automatic Check actuator and replace if necessary.
Economizer Damper Actuator
Direction Switch Wrong
Alert Generated
Automatic Actuator direction control switch (CCW, CW) wrong.
Excess Outdoor Air
Alert Generated
Automatic
Economizer Economizing When It
Should Not
Alert Generated
Automatic
Economizer not Economizing When
it Should
Alert Generated
Automatic
Damper Not Modulating
Alert Generated
Automatic
T415
IAQ Input Out of Range
No IAQ Operations
Automatic Bad sensor, bad wiring, or sensor configured
incorrectly.
T416
OAQ Input Out of Range
No OAQ Operations
Automatic Bad sensor, bad wiring, or sensor configured
incorrectly.
T418
OAU Motor Failure
Alert generated
Automatic Check OAU motors for failure
OAU Dirty Filter
Alert generated
Automatic Check/change OAU filters
OAU Low CFM
Alert generated
Automatic Check OAU air flow
OAU General Alarm
Alert generated Automatic
Check
OAU
A420
Supply VFD Fault
Unit shutdown
Automatic VFD fault occurred, review VFD faults.
LEGEND
ECB
— Economizer Control Board
IGC
— Integrated Gas Controller
IAQ
— Indoor Air Quality
MBB
— Main Base Board
OAQ
— Outdoor Air Quality
OAT
— Outdoor-Air Thermistor
OAU
— Outdoor Air Unit
VFD
— Variable Frequency Drive
Table 14 —
Comfort
Link Alarm Codes (cont)
ALARM
OR
ALERT
NUMBER
DESCRIPTION
ACTION TAKEN BY
CONTROL
RESET
METHOD
PROBABLE CAUSE
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: ......