Network Troubleshooting; Ystem Roubleshooting; Normal Sequence Of Operation; Ower - Goodman MVC8 Installation Instructions Manual

Submenu Item
Mode (MODE)
CFM (CFM)
NON-COMM (APPLIES ONLY TO A COMMUNICATING COMPATIBLE FURNACE MATCHED
WITH A NON-COMMUNICATING COMPATIBLE SINGLE STAGE AIR CONDITIONER)
Submenu Item
Cool Airflow (CL CFM)
Cool Airflow Trim (CL TRM)
Cool Airflow Profile (CL PRFL)
Cool ON Delay (CL ON)
Cool OFF Delay (CL OFF)
N
ETWORK TROUBLESHOOTING
Communications is achieved by taking the difference between
two dc signals. The signals and transmission lines are re-
ferred to as "data 1" and "data 2". Each transmission line is
biased to approximately 2.5Vdc. During data reception/trans-
mission, the data lines vary between +5V and ground. (When
data 1 is increasing towards +5V, data 2 is decreasing to-
wards ground and when data 1 is decreasing towards ground,
data 2 is increasing towards +5V. Typically, the data 1 line is
approximately 2.6Vdc and the data 2 transmission line is ap-
proximately 2.3Vdc. The voltage difference between data 1
and data 2 is typically 0.2 to 0.6 Vdc.
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
network. 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.
STATUS
Indication (for Display Only; not User Modifiable)
Displays the current furnace operating mode
Displays the airflow for the current operating mode
User Modifiable Options
18, 24, 30, 36, 42, 48, or 60, default
is 18
-10% to +10% in 2% increments,
default is 0%
A, B, C, or D, default is A
5, 10, 20, or 30 seconds, default is
5 seconds
30, 60, 90, or 120 seconds, default
is 30 seconds
•
S
NOTE: Refer to the instructions accompanying the CT
compatible outdoor AC/HP unit for troubleshooting information.
Refer to the Troubleshooting Chart in the back of this manual
for a listing of possible furnace error codes, possible causes
and corrective actions.
N
P
The normal power up sequence is as follows:
•
•
•
•
•
34
Selects the airflow for the non-
communicating compatible single stage AC
unit
Selects the airflow trim amount for the non-
communicating compatible single stage AC
unit
Selects the airflow profile for the non-
communicating compatible single stage AC
unit
Selects the indoor blower ON delay for the
non-communicating compatible single
stage AC unit
Selects the indoor blower OFF delay for the
non-communicating compatible single
stage AC unit
Learn button – Used to reset the network. Depress
the button for approximately 2 seconds to reset the
network.
T
YSTEM ROUBLESHOOTING
S
ORMAL EQUENCE OF
U

OWER

P
115 VAC power applied to furnace.
Integrated control module performs internal checks.
Integrated control module displays 8 8 8 8 8 8 8 8 8 8 on dual 7-segment
display LED's.
Integrated control module monitors safety circuits
continuously.
Furnace awaits call from thermostat. Dual 7-segment
LED's display O O O O O while awaiting call from thermostat.
Comments
O
PERATION