CHUNLAN -B - Page 108

Troubleshooting
- 106 -
Under following conditions, program controlled electric system will automatically detect
failure. Wire controller will display failure codes:
Failure Failure phenomena Failure analysis
3 occurrences
of anti-freeze
protection
When 3 consecutive
such protection
signals are detected
in 1h, AC unit stops,
wire controller
displays E1, you can
only put it into
operation after
re-powerup
Check for normal cooling system; check for bad
contact at ID pipe temperature sensor connection;
check for broken wire or short circuit at sensor; if
normal, check if R6 on indoor board is 10K
ID ambient
temp probe
b
roken wire
(short circuit)
Wire controller
displays E2, put it
into operation after
re-powerup
First check ID ambient temperature sensor connection
for bad contact, check for broken wire or short circuit
in sensor; if normal, check if R7 on ID board is 10K
ID pipe temp
probe broken
wire (short
circuit)
Wire controller
displays E3, put it
into operation after
re-powerup
First check ID pipe temperature sensor connection for
b
ad contact, check for broken wire or short circuit in
sensor; if normal, check if R6 on ID board is 10K
OD pipe temp
probe broken
wire (short
circuit)
Wire controller
displays E4, put it
into operation after
re-powerup
First check OD pipe temperature sensor connection
for bad contact, check for broken wire or short circuit
in sensor; if normal, check if R5 on ID board is 10K
Communication
failure
In case of
communication
failure between main
control board and
wire controller, the
latter displays E5,
and you can only put
it into operation after
re-powerup
Check for reliable welding on main control board CN6
and wire controller CN1 needle seat, reliable insertion
of cards and broken or short circuit of communication
line;
Check for DC12V input on wire controller, DC5V
output on main control board 7805-3 pin, and DC5V
on RG1-3 of wire controller;
Check normal voltage on main control board 2003
driving block;
Check for normal voltage on crystal oscillator pin of
main control board and wire controller;
Check for normal voltage at communication input/output
of main control board and wire controller