MBVC Installation Manual

12
LED LED Status Indication Possible Causes Corrective Action(s) Notes & Cautions
Off
x Normal condition x None x None x None
1 Flash
x Communications
Failure
x Communications Failure x Depress Learn Button
x Verify that bus BIAS
and TERM dipswitches
are in the ON position.
x Depress once quickly
for a power-up reset
x Depress and hold for 2
seconds for an out-of-
box reset
Red
Communications
LED
2 Flashes
x Out-of-box reset x Control power up
x Learn button depressed
x None x None
Off
x No power
x Communications error
x No power to modular
blower
x Open fuse
x Communications error
x Check fuses and circuit
breakers; replace/reset
x Replace blown fuse
x Check for shorts in low
voltage wiring in
modular blower/system
x Reset network by
depressing learn button
x Check data 1/ data 2
voltages
x Turn power OFF prior
to repair.
x See Network
Troubleshooting
section.
1 Steady
Flash
x No network found x Broken/ disconnected
data wire(s)
x Modular blower is
installed as a legacy/
traditional system
x Check communications
wiring (data 1/ data 2
wires)
x Check wire connections
at terminal block
x Verify modular blower
installation type
(legacy/ traditional or
communicating)
x Check data 1/ data 2
voltages
x Turn power OFF prior
to repair
x Verify wires at
terminal blocks are
securely twisted
together prior to
inserting into terminal
block
x See Network
Troubleshooting
section
Rapid
Flashing
x Normal network
traffic
x Control is “talking” on
network as expected
x None x None
Green Receive
LED
On Solid
x Data 1/ Data 2 miss-
wire
x Data 1 and data 2 wires
reversed at modular
blower, thermostat, or
CT™ compatible
outdoor AC/HP
x Short between data 1
and data 2 wires
x Short between data 1 or
data 2 wires and R
(24VAC) or C (24VAC
common)
x Check communications
wiring (data 1/ data 2
wires)
x Check wire connections
at terminal block
x Check data 1/ data 2
voltages
x Turn power OFF prior
to repair
x Verify wires at
terminal blocks are
securely twisted
together prior to
inserting into terminal
block
x See Network
Troubleshooting
section
Communciations Status LED’s
DIAGNOSTICS
Accessing the modular blower’s diagnostics menu provides
ready access to the last six faults detected by the modular
blower. Faults are stored most recent to least recent. Any
consecutively repeated fault is stored a maximum of three
times. Example: A clogged return air filter causes the modu-
lar blower’s motor to repeatedly enter a limiting condition.
The control will only store this fault the first three consecutive
times the fault occurs.
NOTE: It is highly recommended that the fault history be
cleared when performing maintenance or servicing the
modular blower.
NETWORK TROUBLESHOOTING
The ComfortNet™ system is a fully communicating system,
and thus, constitutes a network. Occasionally the need to
troubleshoot the network may arise. The integrated 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.
• Learn button – Used to reset the network. Depress
the button for approximately 2 seconds to reset the
network.
SYSTEM TROUBLESHOOTING
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 list-
ing of possible modular blower error codes, possible causes
and corrective actions.