System Troubleshooting; Equence Of; Peration; Ower - Goodman GMVC950704CX Installation Instructions Manual

LED
Status
1 Flash
Red
Communications
LED
2 Flashes
1 Steady
Green Receive
LED
Flashing
On Solid
The ComfortNet system is a fully communicating system, and
thus, constitutes a network. Occasionally the need to trouble-
shoot the network may arise. The integrated furnace control has
some on-board tools that may be used to troubleshoot the net-
work. These tools are: red communications LED, green receive
(Rx) LED, and learn button.
• Red communications LED – Indicates the status of the
network. The table below indicates the LED status and
the corresponding potential problem.
• Green receive LED – Indicates network traffic. The table
below indicates the LED status and the corresponding
potential problem.
• Learn button – Used to reset the network. Depress the
button for approximately 2 seconds to reset the network.
LED Indication
Off
Normal condition
Communications
Failure
Out-of-box reset
Off
No power
Communications
error
No network found
Flash
Rapid
Normal network
traffic
Data 1/ Data 2
miss-wire
N
ORMAL
Possible Causes Corrective Action(s)
None None
Communications Depress Learn Button
Failure
Verify that bus BIAS
and TERM
dipswitches are in the
ON position.
Control power up None
Learn button
depressed
No power to furnace Check fuses and
circuit breakers;
Open fuse
replace/reset
Communications error
Replace blown fuse
Check for shorts in
low voltage wiring in
furnace/system
Reset network by
depressing learn
button
Check data 1/ data 2
voltages
Broken/ disconnected Check
data wire(s) communications
wiring (data 1/ data 2
Furnace is installed as
wires)
a legacy/ traditional
system Check wire
connections at
terminal block
Verify furnace
installation type
(legacy/ traditional or
communicating)
Check data 1/ data 2
voltages
Control is "talking" on None
network as expected
Data 1 and data 2 Check
wires reversed at communications
furnace, thermostat, wiring (data 1/ data 2
or CT™ compatible wires)
outdoor AC/HP
Check wire
Short between data 1 connections at
and data 2 wires terminal block
Short between data 1 Check data 1/ data 2
or data 2 wires and R voltages
(24VAC) or C (24VAC
common)
S T
YSTEM ROUBLESHOOTING
NOTE: Refer to the instructions accompanying the CT compatible
outdoor AC/HP unit for troubleshooting information.
Refer to the Troubleshooting Chart in the Appendix for a listing of
possible furnace error codes, possible causes and corrective
actions.
N S
ORMAL

EQUENCE OF

P U

OWER

P
The normal power up sequence is as follows:
•
115 VAC power applied to furnace.
47
S O
EQUENCE OF
Notes & Cautions
None
Depress once
quickly for a power-
up reset
Depress and hold
for 2 seconds for
an out-of-box reset
None
Turn power OFF
prior to repair
Turn power OFF
prior to repair
Verify wires at
terminal blocks are
securely twisted
together prior to
inserting into
terminal block
Verify data1 and
data voltages as
described above
None
Turn power OFF
prior to repair
Verify wires at
terminal blocks are
securely twisted
together prior to
inserting into
terminal block
Verify data1 and
data voltages as
described above
O

PERATION

PERATION