Heat Controller A-DVC09SD-0, Service Manual

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DVC/DVH Inverter Mini-Split Heat Controller
22
However, no matter what value T4 is, if the unit
runs with T3<
38°F(3°C) for more than 120
minutes and T3 remains lower than 29°F( - 2°C)
for more than 3 minutes, the unit will enter
defrosting mode whether or not T2 drops more
than 41°F(5°C) or not.
9.4.2 Ending Defrosting Operation:
If any one of the following items is satisfied, the
defrost operation will end and the unit will return
to normal heating mode.
• T3 rises to be higher than TCDE1.
• T3 remains higher than TCDE2 for 80
seconds.
• The unit has run in defrosting mode for
10 minutes.
Indoor units TCDE1 TCDE2
B-DVC/DVH 09, 12 54°F(12°C)
47°F(8°C)
B-DVC/DVH 18, 24 59°F(15°C)
9.4.3 Defrosting Process
：
DVC/DVH 9K,12K:
Compressor
on
off
on
on
on
off
off
off
4-way valve
Outdoor fan
Indoor fan
Indoor fan breeze(10s)
xx
10s
no longer than 10m 30s
FrequencyF8
10s
Frequency F2
Where xx= 60seconds.
DVC/DVH 18K, 24K:
Compressor
on
off
on
on
on
off
off
off
4-way valve
Outdoor fan
Indoor fan
Indoor fan breeze(10s)
xx
no longer than 10m
Frequency F8
30s
10s
10s
Frequency F2
Where xx=60seconds for 18K model
Where xx=90seconds for 24K model
9.5 Evaporator Coil Temp. Protection
When T2> 140°F( 6 0°C), the compressor will
turn off, but will restart when T2< 119°F( 4 8°C).
When T2> 128°F(53°C) , the compressor
frequency will decrease to a lower level and
runs at this level for 20seconds to protect the
unit. When the frequency decreases to
Fmax= F2 and T2>
128°F(53°C) for 3 minutes,
the compressor will turn off. However, when the
coil temperature lowers to T2<
119°F( 4 8°C) or
T2 remains at 119°F( 4 8°C) for 6 minutes, the
frequency will not be limited by the evaporator
coil temperature (T2).
9.6 Auto-Mode
This mode can be selected using the remote
control. The set temperature (Ts) can be
changed between 63-
86°F (17 -3 0°C) .
In auto mode, the machine will choose the
mode according to ΔT, where ΔT =T1 -Ts:
ΔT=T1 -Ts Auto Mode Function:
ΔT >1
°
Cooling
-1 °<ΔT≤1° Fan-only
ΔT≤ -1
°
Heating