Operation Modes And Functions; Fan Only Mode; Cooling Mode - Heat Controller B-DVH09SD-0 Service Manual

Heat Controller
8.3.7 Compressor Crankcase Heater
If the outdoor ambient temperature T4<38°F
(3°C) and the unit connects to a new power
supply or if the compressor has stopped for
over 3 hours, the crankcase heater will turn on.
When T4>41°F (5°C) or the compressor starts
running, the crankcase heater will turn off.
8.3.8 Zero Crossing Detection Error
If the unit detects a time interval is not correct
for a continuous 240s, the unit will stop and the
LED will display the appropriate error code. The
correct zero crossing signal time interval should
be between 6-13ms.
8.4.2.9 Condenser temperature protection
131°F (55°C) <T3<140°F (60°C), the
compressor frequency will decrease until it

9.0 Operation Modes and Functions

9.1 Fan Only Mode

In Fan only mode, the outdoor fan and
compressor stop running. The temperature
setting function is disabled and no setting
temperature is displayed on the indoor unit.
The Indoor fan can be set to high/med/low/auto
in fan only mode. The louver will operate the
same as it does in cooling mode. When the
fan only mode is placed in Auto Mode, it
operates as shown below:
°F (°C)
81.5 (27.5)
27.5
High
80.6 (27) 27
Medium
77.9 (25.5)
25.5
7.7 (25)
25
Low

9.2 Cooling Mode

9.2.1 Compressor Operation-Cooling Mode
The maximum operating frequency (Fmax),
follows the chart below based on the outdoor
ambient temperature T4
reaches level F1 and will continue to run at this
level. When T3<129°F (54°C), the compressor
will keep running at the current frequency.
However, if T3<126°F (52°C), the compressor
will not limit the frequency and resume to the
former frequency based on demand. But, if
T3>140°F (60°C) for 5 seconds, the
compressor will stop until T3<126°F (52°C).
8.4.2.10 Evaporator temperature protection
When T2<32°F(0°C), the compressor will stop
and will restart when T2
32°F(0°C) ≤T2≤39°F(4°C), the compressor
frequency will be limited and decreased to the
lower level. However when the temperature is
39°F(4°C)≤T2≤45°F(7°C)≤, the compressor will
keep the current frequency. At T2>45°F(7°C)≤,
the compressor frequency will not be limited.
°F (°C)
113 (45)
45
109.4 (43)
43
104 (40)
40
118.4 (38)
38
88.7 (31.5)
31.5
85.1 (29.5)
29.5
71.6 (22)
22
68 (20)
20
19
17
DVC/DVH Inverter Mini-Split
≥
41°F(5°C). At
Fmax=F4
Fmax=F7
Fmax=F8
Fmax=F6
Fmax=F3