Panasonic U-8MF2E8 Service Manual page 15

3. Compressor Control
3-6-2. Condensation Temperature Adjustment by Roadmap Control
The "B" area's target temperature is different due to cooling, heating and mixed cooling/heating operation.
Cooling
Heating
Mixed cooling/heating
Cooling operation
The purpose of this control at cooling is to prevent abnormal high-pressure.
Condensation temperature area at cooling operation
Tc_tgt_max.
Tc_tgt_min.
Heating operation
The heating capacity is adjusted with this control. It also prevents abnormal high-pressure.
Condensation temperature area at heating operation
Condensation temperature area at heating operation and mixed cooling/heating operation
Tc_tgt_max.
Tc_tgt_min.
* PX is usually fixed to 58 degrees. If the high pressure goes up rapidly after the compressor starts, the system
experiences urgent stop. The next time the system will start with lower PX.
* In the B area, the compressor capacity changes depending on the refrigerant condition.
* When the system operates in a minimum capacity, the system will continue operating for at least 6 minutes
if the condensation temperature area is C area.
* The condensation temperature is not adjusted when there are one or more indoor units that select the test run.
Target lower temperature
(Tc_tgt_min)
53.0°C
48.0°C
48.0°C
deg
Thermostat OFF
Compressor capacity decreases
Compressor capacity cannot increase
Compressor capacity can increase
deg
Thermostat OFF
Compressor capacity decreases
Compressor capacity holds
Compressor capacity can increase
1 - 7
Target upper temperature
(Tc_tgt_max)
55.0°C
51.0°C
51.0°C
C area
B area
A area
C area
B area
A area
3WAY SYSTEM
Control Functions
1