
15
LED
LED Status
Indication
Possible Causes
Corrective Action(s)
Notes & Cautions
Off
• Normal condition
• None
• None
• None
• Depress once quickly for a
power-up reset
• Depress and hold for 2
seconds for an out-of-box
reset
• Control power up
• Learn button depressed
• No power
• No power to furnace
• Check fuses and circuit
breakers; replace/reset
• Communications error
• Open fuse
• Replace blown fuse
• Communications error
• Check for shorts in low
voltage wiring in
heat pump/system
• Reset network by
depressing learn button
• Check data 1/ data 2
voltages
• Broken/ disconnected data
wire(s)
• Check communications
wiring (data 1/ data 2
wires)
• Turn power OFF prior to
repair
• Heat pump is installed as a
legacy/ traditional system
• Check wire connections at
terminal block
• Verify wires at terminal
blocks are securely twisted
together prior to inserting
into terminal block
• Verify heat pump
installation type (legacy/
traditional or
communicating)
• Check data 1/ data 2
voltages
Rapid Flashing
• Normal network traffic
• Control is “talking” on
network as expected
• None
• None
• Data 1 and data 2 wires reversed
at heat pump, thermostat, or
CT compatible indoor unit
• Check communications
wiring (data 1/ data 2
wires)
• Turn power OFF prior to
repair
• Short between data 1 and
data 2 wires
• Check wire connections at
terminal block
• Verify wires at terminal
blocks are securely twisted
together prior to inserting
into terminal block
• Short between data 1 or
data 2 wires and R
(24VAC) or C (24VAC
common)
• Check data 1/ data 2
voltages
• None
Green Receive LED
Off
• Turn power OFF prior to
repair
1 Steady Flash
• No network found
On Solid
• Data 1/ Data 2 miss-wire
Red Communications
LED
• Depress Learn Button
2 Flashes
• Out-of-box reset
• None
1 Flash
• Communications Failure • Communications Failure