48
Cause
Corrective Action
the end terminal on the LS8 circuit (on J15 terminal of relay board).
•
Voltage at the end terminal with no cable indicates the F8 fuse is good and the
circuit is not energized.
•
Make sure the UV LED is on.
•
If the ballast has power and the UV lamp is new, the problem is either cable
connections or the UV ballast.
•
Check Connector B cable connections. If there are no loose terminals, replace the
UV ballast.
No Power to UV
Relay circuit LS8
and K2 relay
•
Absence of voltage at LS8 indicates K2 Relay is open.
•
Check magnetic UV interlock switch on Left side (as you face the cabinet) of sash.
•
Check the AC voltage to and from the K2 relay.
•
Absence of voltage indicates a wiring issue between the RED (Live) power in and the
K2 relay.
•
If voltage to the K2 relay is present, but no voltage out of the K2 relay, this indicates
the relay is not energized or defective.
•
Check the DC voltage to the coil of the K2 relay. Voltage should be 12VDC ± 10%.
•
No voltage indicates the magnetic switch on the Left side is not closed. Check the
wiring to the switch Connector D-6 and D-3.
•
To simulate a closed switch, set the jumper between connector D-6 and D-3 at
Connector D.
•
If the relay does not energize, check the wiring from the K2 coil to Connector D and
the neutral wiring from K2 to the DC Power supply.
•
If wiring connections are OK, visually inspect K2 relay for any burnt or flash marks.
•
If burnt or flash marks are present, replace the relay.
•
If no burnt or flash marks are found, turn off the cabinet.
•
Disconnect relay cables and check for the continuity at K2 relay terminals. See figure
8-2. NC to COM has continuity while, NO to COM does not have continuity. Replace
the relay if any of the terminals are found with wrong continuity configuration.
UV magnetic
switch is defective
or misaligned
•
Move sash to Fully Closed position. The LCD should show
SASH: FULLY CLOSED
.
•
If the LCD display shows “
SASH: NO!
” the sash is not fully closed.
•
Check the magnetic switches. There are 3 magnetic switches behind the right sash
profile cover. See Figure 7-2 above. The bottom one is for UV Mode position.
•
There is a magnet attached to the glass to activate the magnetic switch.
•
Shift the switch or magnet position so the distance between them is between 10-
13mm (3/8” to 1/2”) as explained in Figure 7-2 above. If the distance is too far, the
switch may not be able to detect the magnet.
•
If the LCD still showing “
SASH: NO
” check the connections at Connector D pins D-4
and D-5
•
To simulate a closed U/V Switch, connect the jumper between Connector D pins D-5
and D-4.
•
If this does not turn on the UV, return to the first step and repeat the procedures.
Figure 8-1
Figure 8-2
Summary of Contents for Class II
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