Mitsubishi PUHY-EP250 - Page 108

[5-3 Operation Flowcharts ]
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HWE12050 GB
5 Control
(2) Heating operation
1) When outdoor unit starts defrosting, it transmits defrost operations command to indoor unit, and the indoor unit start defrosting
operations. Similarly when defrosting operation stops, indoor unit returns to heating operation after receiving defrost end com-
mand of outdoor unit.
2) Defrost end condition: 12 minutes have passed since defrost operation started.
Outdoor unit pipe temperature: Refer to the following page(s).[5-2-7 Defrost Operation Control](page 86)
Heating operation
Test run mode
ON
Thermostat ON
Defrost
operation
3-minute restart
prevention
*Note 1,2
*Note 1,2
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
1. Indoor/outdoor unit fan control
2. Inverter frequency control
3. Indoor unit LEV, LEV1,LEV2 control
4. Solenoid valve control
5. 72C control
Normal operation
Defrost operation
4-way valve ON
During test run mode
1. Indoor unit fan operation at
Very Low speed
2. Inverter output 0Hz
3.
Indoor unit LEV, LEV1 Fully closed
LEV2 rated opening
4. All solenoid valves OFF
5. Outdoor unit fan stop
6. 72C OFF
7.
Compressor motor becomes energized.
4-way valve OFF
Stopping the
defrost operation
Stopping the defrost
operation
Return to heating
operation
1. Indoor unit fan stops
2.
I nverter defrost frequency control
3. Indoor unit LEV fully closed.
4. Solenoid valve control
5. Outdoor unit fan stop
6. LEV1 control
7. LEV2
fully opened.
8. 72C control
Unit in the stopped state