Ahc Single Character Display — Error Codes - Lennox CBX40UHV Series Installation And Service Procedure

Table 13. AHC Single Character Display — Error Codes (Communicating and Non-Communicating)
Alert
Alert
Priority
Code
E105 The air-handler has lost communica­
Critical
tion with the rest of the system.
E114 There is a frequency/distortion problem
Critical
with the power to the air-handler.
The 24VAC to the air-handler control is
E115
Critical lower than the required range of 18 to
30VAC.
Moder­ There is a delay in the air-handler re­
E120
ate sponding to the system.
The iComfort™ thermostat has lost
E124
Critical communication with the air-handler for
more than 3 minutes.
E125 There is a hardware problem with the
Critical
air-handler control.
E130 Moder­ An air-handler configuration jumper is
ate missing.
E131 The air-handler control parameters are
Critical
corrupted.
E132 The air-handler control software is cor­
Critical
rupted.
The iComfort™ thermostat has found a
E180
problem with the air-handler outdoor
Critical
sensor.
The system has lost communication
E201
with the or air-handler indoor blower
Critical
motor.
The unit size code for the air-handler
E202
and the size of blower motor do not
Critical
match.
E203 The unit size code for the air-handler
Critical
has not been selected.
The air-handler's blower motor will not
E292
Critical
start.
E295 The indoor blower motor is over heat­
Minor
ing.
There is a problem with air-handle) dis­
E310
Critical
charge air sensor.
The blower cannot provide the re­
E312
Minor
quested CFM due to high static.
The indoor and outdoor unit capacities
E313
Minor
do not match.
How to Clear
Equipment is unable to communicate. This may indicate the existence of other alarms
/ codes. In most cases errors are related to electrical noise. Make sure high voltage
power is separated from RSBus. Check for mis-wired and/or loose connections be­
tween the thermostat, indoor unit and outdoor unit. Check for a high voltage source
of noise close to the system. Generally, this is a self-recoverable error.
This alarm/code may indicate transformer overloading. Check the voltage and line
power frequency. Check the generator operating frequency, if the system is running
on back-up power. Correct voltage and frequency problems. System resumes normal
operation 5 seconds after fault recovered.
24-volt power low (range is 18 to 30 volts). Check and correct voltage. Check for addi­
tional power-robbing equipment connected to system. This alarm / code may require
the installation of an additional or larger VA transformer.
Typically, this alarm/code does not cause any issues and will clear on its own. The
alarm/code is usually caused by a delay in the outdoor unit responding to the thermo­
stat. Check all wiring connections. Cleared after unresponsive device responds to
any inquiry.
Equipment lost communication with the iComfort
nections, ohm wires and cycle power. The alarm stops all associated HVAC opera­
tions and waits for a heartbeat message from the unit that's not communicating. The
alarm/fault clears after communication is re-established.
There is a control hardware problem. Replace the control if the problem prevents op­
eration and is persistent. The alarm/fault is cleared 300 seconds after the fault recov­
ers.
Configuration jumper(s) missing on control (applicable in non-communicating ap­
plications only). Replace the jumper or put wire between terminals on control. Cleared
after jumper is connected.
Reconfigure the system. Replace the control if heating or cooling is not available.
Recycle power. If failure re-occurs, replace the control. System reset is required to
recover.
In normal operation after control recognizes sensors, the alarm will be sent if valid
temperature reading is lost. Compare outdoor sensor resistance to temperature/re­
sistance charts in unit installation instructions. Replace sensor pack if necessary. At
the beginning of (any) configuration, the air-handler control will detect the presence
of the sensor(s). If detected (reading in range), appropriate feature will be set as
installed and shown in the 'About' screen. The alarm / fault will clear upon configura­
tion, or sensing normal values.
Lost communication with indoor blower motor. Possible causes include power out­
age, brown-out, motor not powered, loose wiring, condensation on air handler control
without cover on breaker. Problem may be on control or motor side. Cleared after
communication is restored.
Incorrect appliance unit size code selected. Check for proper configuring under unit
size codes for air handler on configuration guide or in installation instructions. The
alarm / fault clears after the correct match is detected following a reset. Remove the
thermostat from the system while applying power and reprogramming.
No appliance unit size code selected. Check for proper configuring under: Unit size
codes for air handler on configuration guide or in installation instructions. Critical
Alert. The alarm/fault clears after the correct match is detected following a reset. Re­
move the thermostat from the system while applying power and reprogramming.
The system will go into watchguard mode. Indoor blower motor unable to start. This
could be due to seized bearing, stuck wheel, obstruction etc. Replace motor or wheel
if assembly does not operate or meet performance standards. The alarm/fault clears
after the indoor blower motor starts successfully.
Indoor blower motor over temperature (motor tripped on internal protector). Check
motor bearings and amps. Replace if necessary. The alarm / fault clears after blower
demand is satisfied.
Compare outdoor sensor resistance to temperature/resistance charts in installation
instructions. Replace sensor if necessary. The alarm/fault is cleared 30 seconds after
fault is detected as recovered.
Warning Only. Restricted airflow - Indoor blower is running at a reduced CFM (cut­
back mode). The variable-speed motor has pre-set speed and torque limiters to pro­
tect the motor from damage caused by operating outside of design parameters (0 to
0.8" e.g.. total external static pressure). Check filter and duct system. To clear, replace
filter if needed or repair/add duct. The alarm/fault is cleared after the current service
demand is satisfied.
Check for proper configuring in installation instructions. Alarm is just a warning. The
system will operate, but might not meet efficiency and capacity parameters. The
alarm will clear after commissioning is complete.
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thermostat. Check the wiring con­
CBX40UHV