Wet Operation Protection - Daikin FTK25JVE9 Service Manual

Si04-115
1.18

Wet Operation Protection

Outline The lower limit of output frequency is limited in two steps in accordance with outdoor conditions
in order to secure the reliability of compressor (suction dryness and differential pressure).
Processing 1. at the first step
"
"
2. at the second step
"
"
3. The set of a constant
DOA1CG, DOA2CG, DOA3CG, FCG7 and FCG8 have constants for Cooling /Heating
separately and these constants are distinguished with a suffix c/w.
4. Actual constant
∗
Main Function
During operation of compressors.
Outdoor temperature ≤ DOA1CG
If and are under the simultaneous condition with AND, the lower limit of frequency in
this function is set at FCG7.
Compressors stop.
Outdoor temperature ≥ DOA2CG
If and are under the simultaneous condition with OR, the lower limit of frequency at the
first step control is cancelled.
During operation of compressors
Outdoor temperature ≤ DOA3CG
If and are under the simultaneous condition with AND, the lower limit of frequency in
this function is set at FCG8.
Compressors stop.
Outdoor temperature ≥ DOA4CG
If and are under the coordinate condition with OR, the lower limit of frequency at the
second step control is cancelled.
Outdoor temperature
DOA2CG
DOA1CG
DOA4CG
DOA3CG
The lower frequency limit.
(In cooling)
J type 25 / 35
DOA1CGC
DOA2CGC
DOA3CGC
DOA4CGC
FCG7C
FCG8C
DOA : Outdoor air temperature
CGC : Compressor guard for cooling
CGW : Compressor guard for heating
FCG : Frequency guard for compressor protection
FCG7 FCG8
18°C DOA1CGW
20°C DOA2CGW
14°C DOA3CGW
16°C DOA4CGW
34Hz
34 Hz
General Functionality
FCG7 Cancelled
(In heating)
J type 25 / 35
FCG7W
FCG7W
(R1922)
0°C
2°C
-4°C
-2°C
48 Hz
54 Hz
39