– 38 –
AUTO-FRESH DEFROST
●
During heating operation is stopped, and when auto-fresh condition is established, defrost operation will be
performed while operation is stopped.
Auto-fresh consists of balancing period at start of defrost for [TDF414] seconds Æ Reverse cycle period for MAX
12 minutes.
(1) Start conditions for auto-fresh
●
When all the following conditions are established, auto-fresh is executed:
1
Defrost request signal is present.
2
All indoor units are stopped.
3
15 minutes of auto-fresh inhibit period has elapsed.
4
Compressor is ON when operation is stopped.
5
Compressor delay command is sent from indoor unit when operation is stopped.
(2) Release condition of auto-fresh
●
If any one of following conditions is established, auto-fresh is released:
1
Heat exchange temperature returns (heat exchange temperature
⭌
DEFOFF)
2
12 minutes of defrost MAX time has elapsed.
3
Failure occurred.
4
Either unit 1 or unit 2 started operation.
❈
Released during start of balancing period : Stopped or started after remaining balancing period has
elapsed.
❈
Released during reverse cycle period
: Stopped or started after balancing for 3 minutes.
(3) Outputs during auto-fresh
[Indoor unit defrost request]
:
Transmitted only to unit to which auto-fresh is applied indoor unit
stopped last).
[Compressor]: Accelerated by DFSTEP rpm/TDFSPT seconds and reaches defrost MAX speed [DEFMAX].
[Electric expansion valve]:
Unit auto-fresh not applied: FULL CLOSE when balancing for 30 seconds has elapsed at start of defrost.
Unit auto-fresh applied: Synchronized with step-up of rotation speed of compressor, opened by [pulses
and reaches MAX opening degree [DEFSMX] when rotation speed of compressor
reaches [DEFMAX].
(4) Note
●
Shifted to auto-fresh in defrost mode when operation is stopped.
●
All indoor units must be stopped to fulfill condition for auto-fresh.
If signal is delayed, auto-fresh condition will not be established.
Содержание RAM-18QH5E
Страница 9: ... 8 ...
Страница 10: ... 9 RAM 18QH5E MODEL RAM 18QH5E ...
Страница 11: ... 10 ...
Страница 12: ... 11 AC 220V 240V ONLY L N INDOOR 1 C1 D1 C2 D2 INDOOR 2 RAM 18QH5E ...
Страница 13: ... 12 RAM 18QH5E ...
Страница 21: ... 20 MODEL RAM 18QH5E WIRING DIAGRAM OUTDOOR UNIT ...
Страница 23: ...PRINTED WIRING BOARD LOCATION DIAGRAM MODEL RAM 18QH5E 23 MOUNTING PCB SET TYPE ...
Страница 25: ... 27 heating ff BASIC MODE MODEL RAM 18QH5E ...
Страница 28: ... 33 Table 6 Table 7 ...
Страница 29: ... 35 ...
Страница 31: ... 37 ...
Страница 56: ... 62 Fig 11 2 ...
Страница 69: ... 75 1 Outdoor unit does not operate remote control signal can be received RAM 40QH5 ...
Страница 71: ... 77 Lighting mode self diagnosis lamp 2 RAM 18QH5E ...
Страница 72: ... 78 TROUBLESHOOTING OF THE SYSTEM POWER MODULE ...
Страница 73: ... 79 ...
Страница 74: ... 80 ...
Страница 75: ... 81 ELECTRIC EXPANSION VALVE PIPE THERMISTOR POSITION CHARTS MODEL RAM 18QH5E ...
Страница 78: ...HITACHI PM NO 0276E Printed in Malaysia RAM 18QH5E ...