WattMaster WM-WCC3-TGD-01B - Manual (Page 796)

VAV/Zone Controller Technical Guide
Operator Interface 28
Troubleshooting
Using LEDs To Verify Operation
The VAV/Zone controller is equipped with LEDs that can be used as
very powerful troubleshooting tools. The VAV/Zone Controller board has
three LEDs. Two of these LEDs are used in troubleshooting. See Figure
16 for the LED locations. The LEDs and their uses are as follows:
“REC”
This LED will light up to indicate system communications.
“PWR”
This LED will light up to indicate that 24 VAC power has been applied
to the controller.
“SCAN”
This is the diagnostic blink code LED. It will light up and blink out
diagnostic codes.
SP
ACE
SENSOR
PJ3
D5
C9
C10
C1
1
TB2
AIN C13
R10
R14
R15
R19
R20
R18
SCAN
REC
C6
“SCAN”
Diagnostics LED
“REC” LED
“PWR” LED
Figure 16: LED Locations
“REC” LED Operations
When the controller is communicating, this LED will fl icker.
“PWR” LED Operations
When the VAV/Zone Controller is powered up, the “PWR” LED should
light up and stay on continuously. If it does not light up, check to be
sure that the connector is connected to the board and that the connections
are tight. Be sure power is connected and turned on. If after making all
these checks, the “PWR” LED does not light up, the board is probably
defective.
“SCAN” LED Operations
As previously described, when the board is fi rst powered up, the LED
will do the following:
• Extinguished for a few seconds
•
SCAN LED blinks the board address (Address 14 = 14
blinks)
•
5 second pause
•
Damper calibration - LED blinks slowly as damper moves
towards the open position. The LED blinks fast as the damper
moves towards the closed position.
After the above steps, the status code is repeatedly blinked every 10
seconds to indicate controller status. The status blink codes are listed
in Table 5 below in order of priority.
LED Blinks This Number of
Times
Blink Code Description
1 Normal Operation. No
Alarm Conditions Exist
2 Push-Button Override Or
Group Override Is Active
4 Bad Airfl ow Sensor
5 Bad Or Missing Space
Sensor
6 Damper Failure
7 Damper Feedback Failure
:
Table 5: SCAN LED Blink Codes
Only the highest priority failure code will be shown. You must correct
the highest priority alarm before other problems will be indicated.
If the “SCAN” LED does not operate as indicated above, fi rst check the
address switch setting. See Figure 10 on page 15 for correct address
switch setting procedures. If the address switch setting is correct and the
“SCAN” LED still does not behave as indicated above, contact WCC
III Controls Technical support.
NOTE: Power to the controller being addressed must always be
cycled after changing address switch settings in order for
the changes to take effect.