AdvantagePlus Fault Tree Troubleshooting
1706.doc
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24 VAC LED is off; does not have 24VAC out of the transformer
Explanation: This LED monitors voltage from the transformer. The LED is ON
when secondary 24VAC is present. You may have line voltage and not have the
24VAC line lit if the board is bad.
At a minimum, check the following:
Transformer wiring
Reseat plugs on control module (CN4)
Unit appears to be OK. Recycle power.
Is the green LED on
the bottom left side
of the control board
lit up?
Yes
No
Replace control board
Remove and check wall plug. Ensure the black lead is to the brass
screw; the white lead is to the silver screw; and there is a ground
wire present.
Check the wiring connections inside the blue plastic junction box
on the heater. Black to black, white to white; ground to green.
If the green LED is not ON, then the unit thinks polarity is not
correct.
Continue to next step
Is there 120 VAC line
voltage from the board to
the transformer?
Yes
No
Replace board
Measure for 120 VAC at the black and white wires of CN4
