Super Multi System - Toshiba
Super Multi System - Toshiba
Super Multi System - Toshiba
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Control features<br />
Outdoor unit<br />
No. Control Description Diagram<br />
1 Defrost During heating operation, defrost is<br />
(Heating mode) controlled by the outdoor unit heat<br />
exchanger temperature sensor (TE).<br />
When the cumulative operating time with<br />
TE in zone [A] has amounted to 25 minutes,<br />
defrost operation starts. Subsequent<br />
defrosts occur after a cumulative time of 55<br />
minutes. When heating operation resumes<br />
after defrost, the timer is reset.<br />
The maximum defrost period after TE<br />
returns to zone [B] is 1 minute.<br />
Heating operation resumes immediately<br />
after TE returns to zone [C].<br />
2 Oil retrieval During cooling operation, oil retrieval is<br />
(Cooling mode) performed if one or more Indoor units are<br />
OFF.<br />
If this condition is satisfied, when cooling<br />
operation commences, oil retrieval takes<br />
place for 1 minute.<br />
If cooling operation continues, oil retrieval is<br />
repeated for 1 minute every 60 minutes.<br />
During oil retrieval the following occurs:<br />
a. All <strong>Multi</strong> Controller PMVs are opened.<br />
The degree of opening is dependant<br />
on the capacity of the Indoor unit .<br />
b. If the D.O.L. compressor is OFF the<br />
inverter compressor speed increases<br />
to SD.<br />
When cooling operation ends the timer is<br />
reset.<br />
3 <strong>Super</strong>heat control <strong>Super</strong>heat is controlled by the <strong>Multi</strong><br />
(Cooling mode) Controller for cooling operation.<br />
The level of superheat is determined by the<br />
difference between the evaporator outlet<br />
temperature for each indoor unit (ThA, B,<br />
C, D) and the saturation temperature (ThX).<br />
If the superheat of an indoor unit enters<br />
zone [Y], the relevant M/C PMV opens<br />
further to compensate for this increase. The<br />
degree of additional opening is dependant<br />
on the capacity of the indoor unit.<br />
When zone [Z] is reached the PMV opening<br />
is held at the level set in zone [Y].<br />
When the level of superheat returns to zone<br />
[X] the control is cancelled.<br />
Temp.<br />
(°C)<br />
Oil<br />
retrieval<br />
12<br />
8<br />
-3<br />
<strong>Super</strong>heat<br />
(°C)<br />
A<br />
Cooling mode<br />
C<br />
B<br />
60 min. < 60 min.<br />
1 min. 1 min.<br />
13<br />
9<br />
Y<br />
X<br />
Oil<br />
retrieval<br />
Z<br />
Compr.<br />
off<br />
Timer<br />
reset<br />
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