![Hitachi RAM-55QH5 Service Manual Download Page 55](http://html.mh-extra.com/html/hitachi/ram-55qh5/ram-55qh5_service-manual_2139489055.webp)
– 64 –
Time chart when executing defrost ( unit 1, unit 2 and unit 3 operated)
Time chart when executing defrost ( Only unit 1 operated, unit 2 and unit 3 stopped)
Unit 1
Unit 1
Unit 2
Unit 3
Unit 1
Unit 2
Unit 3
Unit 1
Unit 2
Unit 3
Compressor
rotation speed
Outdoor fan
Heating output
Cooling output
Defrosting signal
Request
Reversing
valve
Operation
Compressor
Turns on for
cooling
Unit 2
Unit 3
Electric expansion valve
480
0
Hold
Hold 500ms
DFCTPS$
DFPSMX$
Balancing period [TDF415] sec.
Outdoor temperature ≥ STAROTP_W SDRCTI_W1
Outdoor temperature ≤ STAROTP_W SDRCTI_W2
Balancing period [TDF414] sec.
Defrosting inhibit period
Start sequence
T_DFCTPS
DEFMAX
Reverse cycle period (max. 12 minutes)
TSKTM2
SDRCT2
30sec.
15sec.
Defrosting sequence
DFSTEPmin
-1
/
TDFSPT sec.
Defrosting request
Defrosting request
Defrosting request
T_4BEN_DEF
DFPSMX$
DFPSMX$
DFCTPS$
DFCTPS$
DFSPPS$ Pulse
DFCTPS$
DFCTPS$
DFCTPS$
PSTARTH$
PSTARTH$
PSTARTH$
DFSPPS$ Pulse
DFSPPS$ Pulse
Hold 500ms
Hold 500ms
Hold
Hold
480
0
480
0
Outdoor temperature ≥ STAROTP_W TSKTMI_W1
Outdoor temperature ≤ STAROTP_W TSKTMI_W2
Unit 1
Unit 1
Unit 2
Unit 3
Unit 1
Unit 2
Unit 3
Unit 1
Unit 2
Unit 3
Compressor
rotation speed
Outdoor fan
Heating output
Cooling output
Defrosting signal
Request
Reversing
valve
Operation
Compressor
Turns on for
cooling
Unit 2
Unit 3
Electric expansion valve
480
0
Hold
Hold 500ms
DFCTPS$
DFPSMX$
Balancing period [TDF415] sec.
TSKTM1-W1
SDRCT1-W1
Balancing period [TDF414] sec.
Defrosting inhibit period
Start sequence
T_DFCTPS
DEFMAX
Reverse cycle period (max. 12 minutes)
TSKTM2
SDRCT2
30sec.
15sec.
Defrosting sequence
DFSTEPmin
-1
/
TDFSPT sec.
Defrosting request
T_4BEN_DEF
DFSPPS$ Pulse
DFCTPS$
PCLOSH$
PCLOSH$
PSTARTH$
480
0
480
0
30sec.
MODEL RAM-65QH5
Summary of Contents for RAM-55QH5
Page 31: ... 30 CAPACITY DIAGRAM RELATED TO THE PIPING LENGTH MODEL RAM 65QH5 ...
Page 37: ...CIRCUIT DIAGRAM MODEL RAM 55QH5 39 L C023 C022 C002 C001 C025 C024 N ...
Page 38: ...CIRCUIT DIAGRAM MODEL RAM 65QH5 41 L C023 C022 C002 C001 C025 C024 N ...
Page 41: ... 45 ...
Page 46: ... 51 Outdoortemperature STAROTP_C TSKTM1_C1 Outdoortemperature STAROTP_C TSKTM1_C2 ...
Page 47: ... 53 ...
Page 48: ... 55 ...
Page 49: ... 57 ...
Page 50: ... 59 ...
Page 68: ... 77 5A ...
Page 75: ... 84 ...
Page 76: ... 85 5 Reversing valve control circuit Fig 5 1 ...
Page 91: ... 103 ...
Page 92: ... 104 ...
Page 98: ... 110 TROUBLESHOOTING OF THE SYSTEM POWER MODULE ...
Page 99: ... 111 ...
Page 100: ... 112 ...
Page 102: ... 114 three three inlet 3 Cut off the three pipes at the side and bottom of Reversing valve ...
Page 103: ... 115 ELECTRIC EXPANSION VALVE PIPE THERMISTOR POSITION CHARTS MODEL RAM 55QH5 MODEL RAM 65QH5 ...
Page 108: ...HITACHI PM NO 0312E Printed in Malaysia RAM 55QH5 RAM 65QH5 ...