
ERROR CODES AND ALARM STATUS
Unit Control Panel
The display shown below has four (4) digits. The left two digits indicate the error code (1 to 24), The On/Off icons above
these two digits indicate the currents state of the error code. The right two digits show the history count (up to 99) of the
associated error code. The display contains a maintenance icon (wrench) that will illuminate to indicate when the unit
needs maintenance.
Error
Code
Problem
Action
1
Front Panel Button Stuck For More Than 20 Seconds
Continue to Monitor for “OPEN” (Unstuck) switch. Do not process switch input.
2
Input Voltage Out of Specification (103-127/187-253
Unit stops, open all relays until voltage is back within specs then resume
operation.
3
Indoor Temperature Sensor is Open or Shorted
Unit defaults to 75°F in COOLING or 68°F in HEATING and will continue to
operate.
4
Indoor Coil Temperature Sensor is Open or Shorted
The unit’s control board defaults 40°F. It will override the sensor and the unit will
continue to operate.
5
Outdoor Coil Temperature Sensor is Open or Shorted
The unit defualts to 20°F, overriding the sensor. The unit will continue to operate.
Using Elec Heat if available for HEATING. If not available, it will use HEAT PUMP
if the outdoor temperature allows.
6
Outdoor Coil > (greater than) 175°F
The unit will shut down for 5 minutes. Resume operation for 3 minutes. If test fails
3 times, the severity is increased and the unit operation is locked out.
7
Indoor Coil < (less than) 30°F for 2 consecutive
minutes
The compressor will turn off and the High Fan speed will run. When coil temp
reaches 45°F the unit will resume operation after lockout time.
8
Unit Cycles > (greater than) 9 Times per hour
The unit will continue to operate and be monitored.
9
Unit Cycles < (less than) 3 Times per Hour
The unit will continue to operate and be monitored.
10
Room Freeze Protection
Only use if Electric Heat is available. Run High Speed and Electric Heat until room
temp reaches 46°F. The unit will display “FRZ” during operation. Logged Only.
11
WallStat Problem or Connection Issue
The unit will not operate.
12
Not Applicable
Not Applicable
13
High Pressure LImit Switch is Open
If unit is cooling or heat pump is on, shut down compressor. Run high fan until
switch closes, then resume operation. The third occurance in 1 hour locks unit out.
Applicable to 24K unit only.
14
Not Applicable
Not Applicable
15
Heat Pump Error
If indoor coil temperature is less than ambient temperature for 3 minutes the unit
will use electric heat to satisfy the heating demand.
16
Temperature Beyond Operating Limits
Occurs if the ambient temperature range falls below 0°F or greater than 130°F.
The error code will remain on until the temperature reaches the operating range
and then the unit will return to normal operation.
17
Equipment Doesn’t Meet Minimum Configuratio
The compressor must be enabled and have at least 2 fan speeds
18
Not Applicable
Not Applicable
19
Not Applicable
Not Applicable
20
Not Applicable
Not Applicable
21
Not Applicable
Not Applicable
22
Outdoor Coil Temperature < 30°F for 2 consecutive
Minutes
Unit will use electric heat to satisfy heating demands until the tempearture equals
or exceeds 45°F. Applicable for Heat Pump models only.
23
Frost Protection
Unit will run active defrost for a minimum of 6 minutes when Heat Pump run time is
greater than 60 minutes and outdoor coil temperature is 26°F or less.
24
Not Applicable
Not Applicable
18