Error Code Description
04
Discharge air sensor temperature is out of normal operating range. This can indicate an
open sensor, a short in the wiring, or a circuit board which is out of calibration. Take an
ohm reading across the sensor to ensure proper operation, check the wiring, and verify the
value in L035. Compare the sensor reading to the value in L112 to verify proper calibration
of the circuit board. Approximate ohm readings are 70° F = 1,199 ohms; 80° F = 941 ohms;
95° F = 646 ohms.
05
Outdoor sensor (direct wired) temperature reading is out of normal operating range.
The sensor circuit may be open or shorted, or the processor control board may be out
of calibration. Otherwise, verify that the outdoor sensor is connected to OS and SC on
the 12-position terminal block. Compare the sensor reading to the value in L113 to verify
proper calibration of the circuit board. Approximate ohm readings are 5° F = 7,646 ohms;
50° F = 2,024 ohms; 95° F = 646 ohms.
06
Outdoor temperature reading from the transmitting device (PLC system) is out of normal
operating range. Check the outdoor sensor attached to the transmitting device and the
transmitter for proper operation.
07
Main processor control board temperature sensor is out of normal operating range. Verify
that none of the clearances have been violated and inspect the condition of the processor
control board.
08
External duct sensor temperature is out of normal operating range. This can indicate an
open sensor, a short in the wiring, or the relay driver board is out of calibration. Take an
ohm reading across the sensor to ensure proper operation, check the wiring, and verify the
value in L053. Compare the sensor reading to the value in L144 to verify proper calibration
of the circuit board. Approximate ohm readings are 60° F = 1552 ohms; 70° F = 1199 ohms;
80° F = 941 ohms. Max 190°F, Min 0°
09
Auxiliary analog input is out of normal operating range. Currently not used.
10
Discharge air temperature has exceeded maximum standard operating temperatures.
11
Core C thermocouple temperature is out of normal operating range. An open, shorted, or
otherwise defective thermocouple or a circuit board which is out of calibration can cause
this. Check the thermocouple by taking a millivolt reading of the thermocouple. Compare
the thermocouple reading to the value in L136 to verify proper calibration of the circuit
board. Approximate DC mV readings are 200° F = 3.8 mV; 700° F = 15.2 mV; 1200° F = 27.0
mV. Max. 1720°F, min 0°F.
12
Core D thermocouple temperature is out of normal operating range. An open, shorted, or
otherwise defective thermocouple or a circuit board which is out of calibration can cause
this. Check the thermocouple by taking a millivolt reading of the thermocouple. Compare
the thermocouple reading to the value in L137 to verify proper calibration of the circuit
board. Approximate DC mV readings are 200° F = 3.8 mV; 700° F = 15.2 mV; 1200° F = 27.0
mV. . Max. 1720°F, min 0°F.
13
Core E thermocouple temperature is out of normal operating range. An open, shorted, or
otherwise defective thermocouple or a circuit board which is out of calibration can cause
this. Check the thermocouple by taking a millivolt reading of the thermocouple. Compare
the thermocouple reading to the value in L138 to verify proper calibration of the circuit
board. Approximate DC mV readings are 200° F = 3.8 mV; 700° F = 15.2 mV; 1200° F = 27.0
mV. Max. 1720°F, min 0°F.
14
Core F thermocouple temperature is out of normal operating range. Not used in 9100
Series.
15
Core G thermocouple temperature is out of normal operating range. Not used in 9100
Series.
T
herm
e
lecT
h
ydronic
a
ppendix
| a.11
