Page 47
XP21 SERIES
Heat Pump Control
LEDs
Clearing Status
Solution
Possible
Cause(s)
Condition
icomfort
Touch
®
Thermostat
Display
DS15
Yellow
Clearing Status
Solution
Possible
Cause(s)
Condition
icomfort
Touch
®
Thermostat
Display
DS13
Red
4 flashes
then pause
Off
Critical Alert
Code 404
Locked rotor
Compressor has
a locked out due
to run capacitor
short, bearings
are seized,
excessive liquid
refrigerant.
1
Run capacitor has failed.
2
Low line voltage (contact utility if voltage at discon-
nect is low).
S
Check wiring connections
3
Excessive liquid refrigerant in the compressor.
4
Compressor bearings are seized.
Clears after
power reset or
four normal
compressor
cycles.
5 flashes
then pause
Off
Critical Alert
Code 405
Open circuit
Compressor has
an open circuit
due to power dis-
connection, fuse
is open or other
similar conditions.
1
Outdoor unit power disconnect is open.
2
Unit circuit breaker or fuse(s) is open.
3
Unit contactor has failed to close.
S
Check compressor contactor wiring and
connectors
S
Check for compressor contactor failure
(burned, pitted or open)
S
Check wiring and connectors between supply
and compressor
S
Check for low pilot voltage at compressor
contactor coil
4
High pressure switch is open and requires manual
reset.
5
Open circuit in compressor supply wiring or
connections.
6
Unusually long compressor protector reset time
due to extreme ambient temperature.
7
Compressor windings are damaged.
S
Check compressor motor winding resistance
Clears after one
normal com-
pressor run
cycle or power
reset.
6 flashes
then pause
Off
Critical Alert
Code 406
Open start
circuit
Current not
sensed by Start
transformer.
1
Run capacitor has failed.
2
Open circuit in compressor start wiring or
connections.
S
Check wiring and connectors between supply
and the compressor
S
terminal
3
Compressor start winding is damaged.
S
Check compressor motor winding resistance
Clears when
amperage is de-
tected in RUN
and START
sensors, or after
power reset.
7 flashes
then pause
Off
Critical Alert
Code 407
Open run
circuit
Current not
sensed by run
transformer.
1
Open circuit in compressor start wiring or
connections.
S
Check wiring and connectors between supply
and the compressor
R
terminal
2
Compressor start winding is damaged.
S
Check compressor motor winding resistance
Clears when
amperage is de-
tected in RUN
and START
sensors, or after
power reset.
8 flashes
then pause
Off
Critical Alert
Code 408
Welded
contactor
Compressor
always runs
1
Compressor contactor failed to open.
2
Thermostat demand signal not connected to mod-
ule.
Clears after one
normal com-
pressor run
cycle or after
power reset.
9 flashes
then pause
Off
Moderate/
Critical Alert
3
Code 409
Secondary low
voltage
24VAC is below
18VAC.
1
Control circuit transformer is overloaded
.
2
Low line voltage (contact utility if voltage at discon-
nect is low).
S
Check wiring connections
Clears after volt-
age is higher
than 20VAC for
two seconds, or
after power re-
set.
Fast simultaneous flashing of DS11,
DS13, DS14 and DS15
OEM Mode
Factory test mode.
1. Pause duration is two (2) seconds.
2. Fast flash duration is 1/2 second. Slow flash duration is one (1) second.
3. Initially a moderate status is displayed and is escalated to critical if alarm exists for more than 10 minutes.