Testing Communication Circuit
If an Error E7 occurs, perform the following test to determine
if the indoor control board is functioning properly to send data
to the outdoor unit.
Perform this test with the unit powered and all wiring
connected between indoor and outdoor unit.
Make sure all wiring between the indoor and outdoor unit
are correct. There should no splices between the indoor and
outdoor unit wiring connecting terminals 1 or 3. Make sure
wiring is correct, before performing this test.
1.
Measure the DC voltage between terminals 1 and 3
on the indoor terminal block.
2.
The voltage should fluctuate between 8VDC
and 23VDC. The fluctuating signal indicates a good
communication path.
3.
If the voltage does not fluctuate, and the wiring is
good, the indoor board is defective.
SLIM DUCT TESTING PROCEDURES
TESTING
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