Friedrich VRP Series Service & Parts Manual page 69

Diagnostic Codes
Diag Description
44 Compressor Start Failure
45 Compressor Current Limiter
46 Indoor Coil > 175°F for 5 consecutive
minutes
47 Compressor I2T Fault.
48 Indoor Fan I2T Fault.
49 Outdoor Fan I2T Fault.
50 Motor Board Processor Over Voltage (15V
Rail)
51 Motor Board DC Bus Over Current
52 Motor Board DC Axix Over Voltage
53 Motor Board AC Line Under Voltage
54 Motor Board AC Line Over Voltage
69
TROUBLESHOOTING
Diagnostic Check point
Compressor speed synchronization issue
for 10 consecutive seconds.
The total compressor current exceeds a
set limit.
The T5 sensor reads a temperature
greater than 175°F for 5 consecutive
minutes
N/A.
N/A.
N/A.
N/A.
The DC bus circuit sensed that the current
is too high.
N/A.
The AC input voltage is too low. (< 176 VAC)
The AC input voltage is too high. (> 264
VAC)
Solution
"1. Check compressor wires for damage.
2. Verify connection of the compressor
wires.
3. Replace motor board.
4. Replace compressor."
"This error should automatically correct
itself. If error persists:
1. Check compressor wires for any
damage.
2. Verify resistance of compressor (leg‑leg
and leg‑chassis).
3. Replace the motor board.
4. Replace compressor."
Diagnostic disabled.
Diagnostic disabled.
Diagnostic disabled.
Diagnostic disabled.
"This error should automatically correct
itself. If error persists:
1. Replace the motor board."
Diagnostic disabled.
"This error should automatically correct
itself. If error persists:
1. Verify input voltage to step down
transformer (265V models only)
2. Verify the input voltage to the motor
board.
3. Replace the motor board."
"This error should automatically correct
itself. If error persists:
1. Verify input voltage to step down
transformer (265V models only)
2. Verify the input voltage to the motor
board.
3. Replace the motor board."