Service Manual

– 28 –
–1.5
Tsc or Tsh
+1.5
Heating
(Cooling OFF)
(Cooling ON)
Cooling
Ta ˚C
No.
3
4
5
Item
Room temp.
control
(Continued)
Automatic
capacity control
(GA control)
Automatic
cooling/heating
control
Outline of specifications
2) Using the CODE No. 06, the setup temperature in heating
operation can be corrected.
SET DATA
Setup temp.
correction
0246
+0°C +2°C +4°C +6°C
Setting at shipment
SET DATA 2
1) Based on the difference between Ta and Ts, the operation
frequency is instructed to the outdoor unit.
2) Cooling operation
Every 90 seconds, the room temperature difference
between temperature detected by Ta and Ts and the
varied room temperature value are calculated to obtain
the correction value of the frequency command and then
the present frequency command is corrected.
Ta (n) – Ts (n) : Room temp. difference
n : Counts of detection
Ta (n-1) – Ts (n) : Varied room temp. value
n – 1 :
Counts of detection of 90 seconds before
3) Heating operation
Every 1 minute (60 sec.), the room temperature differ-
ence between temperature detected by Ta and Ts and the
varied room temperature value are calculated to obtain
the correction value of the frequency command and then
the present frequency command is corrected.
Ts (n) – Ta (n) : Room temp. difference
n : Counts of detection
Ta (n) – Ta (n – 1) : Varied room temp. value
n – 1 : Counts of detection of 1 minute before
4) Dry operation
The frequency correction control is same as those of the
cooling operation.
However the maximum frequency is limited to approxi-
mately “S6”.
Note) When LOW is set up, the maximum frequency is
limited to approximately “SB”.
1) The judgment of selecting COOL/HEAT is carried out as
shown below. When +1.5°C exceeds against Tsh 10
minutes and after thermo. OFF, heating operation
(Thermo. OFF) exchanges to cooling operation.
Description in the parentheses shows an example of
cooling ON/OFF.
When –1.5°C lowers against Tsc 10 minutes and after thermo. OFF, cooling operation
(Thermo. OFF) exchanges to heating operation.
2) For the automatic capacity control after judgment of cooling/heating, see Item 4.
3) For temperature correction of room temp. control in automatic heating, see Item 3.
Remarks
Shift of suction
temperature in heating
operation
Tsc: Setup temp. in
cooling operation
Tsh: Setup temp. in
heating operation
+ temp. correction of
room temp. control