York YU2E18YJ6AMHO-Y, Service Manual, Page: 18 / 124

18
If the outdoor ambient temperature is higher than
the set frequency during oil return, the unit stops
the oil return process.
5.3.11 Low Outdoor Ambient Temperature
Protection
When the compressor is off and T4 is lower than -
35
℃
for 10 seconds, the unit stops and displays
“
LP.
”
When the compressor is on and T4 remains lower
than -40
℃
for 10 seconds, the unit stops and
displays
“
LP.
”
When T4 is no lower than -32
℃
for 10 seconds,
the unit exits protection.
5.4 Control and Functions
5.4.1 Capacity Request Calculation
For Old Console series, Old Duct/Cassette/Floor
Ceiling, Old Vertu/Luna Series:
Total capacity Request=Σ(Norm code × HP) /10×
modify rate+ correction
For All new models(New Wall mounted(Hi-Wall)
series, New Duct/Cassette/Console/Floor Ceiling):
Total capacity Request=Σ(Norm code × HP) /40×
modify rate+ correction
Cooling Mode:
T1 Ts
3
1
1
e
c
a
4
2
0
2
3
0
1
f
d
b
Capacity area a b c d e f
Norm code (N) 3 2 1.5 1 0.5 0
Model 9K 12K 18K 24K
HP 1.0 1.2 1.5 2.5
Note: The final result is an integer.
Use the following table and final capacity
request to confirm the operating frequency.
Frequency (Hz)
0
COO
L_F1 COO
L_F2 …
… COOL
_F24
COO
L_F2
5
Amendatory
capacity
demand.
0 1 2
…
…
24 25
The maximum running frequency is adjusted
according to the outdoor ambient temperature
℃
55
54
Fmax=
T4FREMAXC0
51.5
50.5
Fmax= T4FREMAXC1
45.5
44.5
Fmax= T4FREMAXC2
39
38
Fmax= T4FREMAXC3
33
32
Fmax= T4FREMAXC4
30
29
Fmax= T4FREMAXC5
22
20
Fmax= T4FREMAXC6
10
8 Fmax= T4FREMAXC7
0
-2 Fmax= T4FREMAXC8
-10
-12
Fmax= T4FREMAXC9
Fmax= T4FREMAXC10
Heating Mode
T1 Ts
4
0
a
3
1
-1
3
1
2
0
b
c
d
e
f
2