Page 44
506601−01
System fault and lockout LED (DS11 / DS14) alarm codes takes precedence over system status LED codes (cooling, heating stages or
defrost/dehumidification). Only the latest active LED fault or lockout alarm code if present will be displayed. If no fault or lockout codes are active, then system
status LEDs are routinely displayed. See notes 1 and 2 in table below for duration of fast / slow flashes and pause.
Heat Pump Control
LEDs
Solution
Possible Cause(s)
Condition
icomfort
Touch
®
Thermostat
Display
DS11
Green
Solution
Possible Cause(s)
Condition
icomfort
Touch
®
Thermostat
Display
DS14 Red
DS11
Green
Solution
Possible Cause(s)
Condition
icomfort
Touch
®
Thermostat
Display
DS14 Red
Off
1 fast flash
then pause
Not
applicable
First−stage
compressor
heating
These are codes that show status of operation whether the system is operating in either
in first or second stage heating or cooling operation, defrost or in the dehumidification
modes.
Off
2 fast
flashes
then pause
Not
applicable
Second−stage
compressor
heating
On
2 fast
flashes
then pause
Not
applicable
Defrost
1 fast flash
then pause
Off
Not
applicable
First−stage
compressor
cooling
2 fast
flashes
then pause
Off
Not
applicable
Second−stage
compressor
cooling
2 fast
flashes
then pause
On
Not
applicable
Dehumidification
mode
ALERT STATUS
None
Moderate
Alert Code
105
Device
communication
failure
Equipment is unable to communicate. Indicates numerous message errors. 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 between the stat, indoor
unit and outdoor unit. Check for a high voltage source of noise close to the system.
Fault clears after communication is restored.
None
Moderate
Alert Code
120
Unresponsive
device
Usually caused by delay in outdoor unit responding to indoor unit poling.
Recycle power. Check all wiring connections. Cleared after unresponsive
device responds to any inquiry.
None
Critical Alert
Code 124
Active subnet
controller missing
for 180 seconds
Equipment lost communication with the thermostat. Check four wiring connections,
ohm wires and cycle power at the thermostat. Alert stops all services and waits for
heartbeat message from thermostat (subnet controller). Cleared after valid thermostat
(subnet controller) message is received.
None
Critical Alert
Code 125
Hardware Failure
Hardware problem on the control. Cycle power on control. Replace if problem prevents
service and is persistent. Cleared 300 seconds after fault recovered.
None
Moderate /
Critical Alert
Code 126
Internal control
communication
failure
Internal communication on heat pump control. Alert will clear 300 seconds after fault
has recovered.
None
Critical Alert
Code 131
Corrupted control
parameters
Reconfigure the system. Replace control if heating or cooling is not available. Only
applicable in the communicating mode, not in start up. Exit from Commissioning and
Execute ´Set Factory Default mode´. Control will still operate on default parameter set-
tings.
None
Critical Alert
Code 132
Failed flash CRC
check.
Recycle power. If failure re−occurs, replace control. System reset is required
to recover.
Off
Slow flash
Moderate
Alert Code
410
Low pressure
fault
Unit pressures below the lower limit. System is shut down. Clears after pressure switch
closes.
Off
On
Critical Alert
Code 411
Low pressure
switch lockout
Open low pressure switch error count reached 5 strikes. Check system charge using
approach and subcooling temperatures. Reset by putting outdoor unit control in test
mode or resetting low voltage power.
Slow flash
Off
Moderate
Alert Code
412
High pressure
fault
Unit pressure is above the upper limit. System is shut down. Check system operating
pressures and compare to unit charging charts. Clears when pressure switch closes.