Heat Controller B-DVH09SD-0 User manual

SERVICE MANUAL
DVC/DVH 09/12/18/24
Inverter Single Zone
Ductless Mini-Split
AITONS/MARS 35 Brownridge Road, Unit 6, Halton Hills, ON L7G 0C6 • 1-888-744-2911 • [email protected] • www.aitons.com

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DVC/DVH Inverter Mini-Split Heat Controller
TABLE OF CONTENTS
1. Precaution........................................................................................................................................................................3
1.1 Safety Precaution......................................................................................................................................................3
1.2 Warning.....................................................................................................................................................................4
2. Part Identication and Functions...................................................................................................................................5
2.1 Model Numbers of Indoor/Outdoor units...................................................................................................................5
2.2 Required clearances for Indoor/Outdoor units .......................................................................................................5-6
2.3 Features.................................................................................................................................................................6-7
3. Dimensional Data ............................................................................................................................................................8
3.1 Indoor Unit ................................................................................................................................................................8
3.2 Indoor Unit Mounting Bracket ...................................................................................................................................9
3.3 Outdoor Unit............................................................................................................................................................10
4. Refrigerant Cycle Diagram ...........................................................................................................................................11
4.1 Cooling Only Models (DVC).................................................................................................................................... 11
4.2 Heat Pump Models (DVH) ......................................................................................................................................12
5. Wiring Diagrams............................................................................................................................................................13
5.1 Indoor Units........................................................................................................................................................13-14
5.2 Outdoor Units..........................................................................................................................................................15
6. Installation Details.........................................................................................................................................................16
6.1 Electrical .................................................................................................................................................................16
6.2 Line Set Connection Sizes......................................................................................................................................16
6.3 Line Set Lengths and Elevations ............................................................................................................................16
6.4 Field Charging.........................................................................................................................................................16
7. Operating Conditions....................................................................................................................................................17
8. Electronic Display Functions .......................................................................................................................................18
8.1 Abbreviations ..........................................................................................................................................................18
8.2 Display Functions....................................................................................................................................................18
8.3 Main Protection .......................................................................................................................................................18
9. Operation Modes and Functions..................................................................................................................................19
9.1 Fan Only Mode .......................................................................................................................................................19
9.2 Cooling Mode.....................................................................................................................................................19-21
9.3 Heating Mode.....................................................................................................................................................21-23
9.4 Defrost Mode .....................................................................................................................................................23-24
9.5 Evaporator Coil Temp. Protection ...........................................................................................................................24
9.6 Auto-Mode..........................................................................................................................................................24-25
9.7 Dry Mode ................................................................................................................................................................25
9.8 Forced Operation ....................................................................................................................................................25
9.9 Timer Function ...................................................................................................................................................25-26
9.10 Sleep Mode...........................................................................................................................................................26
9.11 Auto-Restart Function............................................................................................................................................26
9.12 Automatic Panel Function .....................................................................................................................................26
9.13 47°F (8°C) Heating................................................................................................................................................26
10. Troubleshooting ..........................................................................................................................................................27
10.1 Indoor Unit Error Codes ........................................................................................................................................27
10.2 Outdoor Unit Errors and Troubleshooting ........................................................................................................28-31
10.3 Diagnosis and Solution ....................................................................................................................................32-48
10.4 Pressure on Service Port ......................................................................................................................................49
WARNING
• InstallationMUSTconformwithlocalbuildingcodesor,intheabsenceoflocalcodes,withtheNationalElectricalCode
 NFPA70/ANSIC1-1993orcurrenteditionandCanadianElectricalCodePart1CSAC.22.1.Whereconictsexist,thelocal
and/or national codes shall prevail.
• Theinformationcontainedinthemanualisintendedforusebyaqualied,licensedservicetechnicianfamiliarwithsafety
 proceduresandequippedwiththepropertoolsandtestinstruments
• Installationorrepairsmadebyunqualiedpersonswillvoidthewarrantyandmaycausehazardsorincorrectoperation.
• Failuretocarefullyreadandfollowallinstructionsinthismanualcanresultinequipmentmalfunction,propertydamage,
personal injury and/or death.

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1. Precaution
1.1 Safety Precaution
To prevent injury to the user or other
people and property damage, the following
instructions must be followed.
Incorrect operation due to ignoring
instruction will cause harm or damage.
Before service the unit, be sure to
read this service manual at first.
1.2 Warning
Installation
Do not use a defective or underrated
circuit breaker. Use this appliance on a
dedicated circuit.
There is risk of fire or electric shock.
For electrical work, contact the dealer,
seller, a qualified electrician, or an
authorized service center.
Do not disassemble or repair the product,
there is risk of fire or electric shock.
Always ground the product.
There is risk of fire or electric shock.
Install the panel and the cover of
control box securely.
There is risk of fire of electric shock.
Always install a dedicated circuit and
breaker.
Improper wiring or installation may cause
electric shock.
Use the correctly rated breaker of
fuse.
There is risk of fire or electric shock.
Do not install, remove, or reinstall the
unit by yourself (customer).
There is risk of fire, electric shock, explosion,
or injury.
Be caution when unpacking and
installing the product.
Sharp edges could cause injury, be especially
careful of the case edges and the fins on the
condenser and evaporator.
Take care to ensure that power cable
could not be pulled out or damaged during
operation.
There is risk of fire or electric shock..
Do not touch (operation) the product
with wet hands..
Do not allow water to run into
electrical parts or the unit.
It may cause fire, failure of the product, or
electric shock.
Do not store or use flammable gas or
combustible materials near the product.
There is risk of fire or failure of product.
Do not use the product in a tightly
closed space for a long time.
Oxygen deficiency could occur.
If abnormal noises or smoke comes
from product, turn the breaker off or
disconnect the power supply cable.
There is risk of electric shock or fire.
Do not open the inlet grill of the
product during operation. (Do not touch the
electrostatic filter, if the is equipped with
one .)
There is risk of physical injury, electric shock,
or product failure..
Turn the main power off when
cleaning or maintaining the product.
There is risk of electric shock.
When the product will not be used for
a long period of time, turn off the circuit
breaker.
There is risk of product damage or failure, or
unintended operation.
CAUTION
Always check for refrigerant leakage
after installation or repair of product.
Low refrigerant levels may cause operational
failure.
Install the drain hose to ensure that
water is drained away properly.
Improper installation may cause water
leakage and damage to personal property.

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Keep the unit level even when
installing the product.
This helps to avoid vibration or water leakage.
Do not install the product where it will
be directly exposed to seaside wind (salty
air).
It may cause corrosion on the product.
Corrosion, particularly on the condenser and
evaporator fins, could cause product
malfunction or inefficient operation.
Operational
Do not block the inlet or outlet of air
flow.
Use a soft cloth to clean. Do not use
harsh detergents, solvents, etc.
There is risk of fire, electric shock, or damage
to the plastic parts of the product.
Do not touch the metal parts of the
product when removing the air filter. They
are very sharp.
Always insert the filter securely.
Clean the filter every two weeks or more
often if necessary.
A dirty filter reduces the efficiency of the air
conditioner and could cause product
malfunction or damage.
Do not insert hands or other objects
through air inlet or outlet while the product
is operated.
Replace the all batteries in the remote
control with new ones of the same type. Do
not mix old and new batteries or different
brands of batteries.
There is risk of fire or explosion.
If battery acid from the batteries gets
onto your skin or clothes, wash it well with
clean water and contact your local poison
control center. Do not use the remote of the
batteries have leaked.

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2. Part Identification and Functions
2.1 Model Numbers of Indoor/Outdoor units
Capacity Indoor Units Outdoor Units
9KBTU/H B-DVH09SD-0 / B-DVC09SD-0 A-DVH09SD-0 / A-DVC09SD-0
12KBTU/H B-DVH12SD-0 / B-DVC12SD-0 A-DVH12SD-0 / A-DVC12SD-0
18KBTU/H B-DVH18SD-1 / B-DVC18SD-1 A-DVH18SD-1 / A-DVC18SD-1
24KBTU/H B-DVH24SD-1 / B-DVC24SD-1 A-DVH24SD-1 / A-DVC24SD-1
2.2 Required Clearances for Indoor and Outdoor units

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2.3 Features
Note:
For Reference Only. Your model may differ and is subject to change.
Cold catalyst filter
Plasma(O)
Silver Ico Filter(O)
Vitamin C Filter(O)
3M HAM Filter(O)
Bio Filter(O)
Golden Fin(O)
Ionizer(O)
Compressor Crankcase Heater(O)
Self Clean(O)
1W Standby
Louver Position Memory Function
Refrigerant Leakage Detect
Self-diag. Function
Hydrophilic Aluminum Fin
Anti-rust Cabinet
Valve Protection Cover
PTC Heating Belt(O)
Horizontal &Vertical Swing Function(O)
Filter
Follow Me(O)
Silent mode(O)
Auto Restart
Turbo Mode
Sleep Mode
Anti-ColdBlow
LowAmbient
Silver Ico Filter
Golden Fin
FollowMe
Self Clean
LowHeating
Room Temp.
Horizontal&VerticalSwingFunction
Refrigerant Leakage Detect
Louver Position Memory Function
Self-Diagnosis Function
Valve Protection Cover
Anti-Rust Cabient
Slump Heater
Compressor Crankcase Heater

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2.3.1 Description of Features and Functions
•Auto-Restart:
The unit will memorize the set conditions before a power failure and resume operation automatically when the
power re-starts.
•Sleep Mode:
This feature helps keep the room conditions at the most desirable levels when you sleep.
•Turbo Mode:
Turbo mode allows the unit to quickly heat or cool and room, at a high speed fan setting.
•Anti-Cold Blow:
In heating mode, this feature prevents cold air from blowing until warm air is ready to be delivered.
•Silver Ion Filter:
The silver filter sterilizes bacteria in the air stream by decomposing cell wall of bacteria.
•Low Ambient Operation:
Allows the unit to operate under low outdoor temperatures.
•Gold Hydrophilic Condensers Fin Coating:
This coating improves the heating efficiency by accelerating the defrosting process. The anticorrosive gold
coating on the condenser helps withstand salty air and corrosive elements for sea side applications.
•Self Clean:
This function wicks away any moisture, essentially cleaning the inside of indoor unit to prevents bacteria for
forming. This feature is especially useful at the end of the season and/or when the unit will not be used for
an extended period of time.
•Follow me:
A temperature sensor is built in the remote control, which signals the unit to automatically change the
operation mode to supply a comfortable temperature.Using this feature allows the unit to sense the
conditions where you are in the room, rather than up high in the room where it traditionally senses the
conditions via the indoor unit.
•Low Room Temperature Protection:
Allows the unit to maintain a set temperature to protect the area it is installed in from freezing when you will be
away for an extended period of time in the winter.
•Louver Swing and Position Memory:
The louvers can swing to make a breeze like affect in the air flow from the indoor unit. When starting the unit
after shutting down, the louver will restore the user’s settings for louver position.
•Refrigerant Leak Detection:
The refrigerant leakage detect function prevents the unit from freezing due to low charge and protects the
compressor from being damaged.
•Self-Diagnosis Function:
The system monitors itself for abnormal operations and turns of the unit automatically to protect it from further
damage, then displays an error code to help troubleshoot the problem for a quick solution.
•Sump Heater:
A PTC heater is installed in the base pan of the outdoor unit to prevent the rain, snow or defrosted water from
accumulating and icing up the unit.
•Compressor Crankcase Heater:
The oil dissolves easily into the refrigerant, especially in low temperature condition, therefore the crankcase
heating belt is used to warm the bottom of the compressor to avoid pumping out too much oil within the
refrigerant, which helps to protect the compressor.

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3. Dimensional Data
3.1 Indoor Unit
Note: The drawings below are only for reference. Actual dimensions may be different and are subject
to change.
WD
H
Note: The above drawing is only for reference. The dimensions of your actual unit may be different
and are subject to change.
Model W D H
B-DVC09SD-0 26.8in
(680mm)
7.0in
(178mm) 10.0in
(255mm)
B-DVH09SD-0
B-DVC12SD-0 30.3in
(770mm)
7.4in
(188mm)
B-DVH12SD-0
B-DVC18SD-1 35.6in
(905mm)
7.8in
(198mm)
10.8in
(275mm)
B-DVH18SD-1
B-DVC24SD-1 40.6in
(1030mm)
8.6in
(218mm)
12.4in
(315mm)
B-DVH24SD-1

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3.2 Indoor Unit Mounting Bracket
Note: The drawings below are only for reference. Actual dimensions may be different and are subject
to change.
LR
H
Model R L H Hole Diameter
B-DVC/DVH09 3.6in(92mm) 6.7in
(170mm) 1.8in
(45mm)
Φ2.56in
(65mm)
B-DVC/DVH12 3.7in(95mm)
B-DVC/DVH18 3.1in(80mm) 3.9in(100mm)
Model R L H Hole Diameter
B-DVC/DVH24 6.4in(163mm) 11.5in(293mm) 1.8in(45mm) Φ2.56in(65mm)
H
L R

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3.3 Outdoor Unit
Note: The drawings below are only for reference. Actual dimensions may be different and are subject
to change.
Note: The above drawing is only for reference. The dimensions of your actual unit may be different
and are subject to change.
Model W H D W1 A B
A-DVC/DVH09
A-DVC/DVH12
26.0in
(660mm)
10.5in
(265mm)
21.25in
(540mm)
28.8in
(732mm)
18in
(458mm)
10.9in
(276mm)
A-DVC/DVH18 30in
(760mm)
11.25in
(285mm)
23.2in
(590mm)
32.5in
(823mm)
20.9in
(530mm)
11.5in
(290mm)
A-DVC/DVH24 33.3in
(845mm)
12.5in
(320mm)
27.6in
(700mm)
35.7in
(908mm)
22in
(560mm)
13.2in
(335mm)

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4. Refrigerant Cycle Diagram
4.1 Cooling Only Models (DVC):
INDOOR OUTDOOR
LIQUID SIDE
GAS SIDE
HEAT
EXCHANGE
(EVAPORATOR)
HEAT
EXCHANGE
(CONDENSER)
COMPRESSOR
CAPILIARY TUBE
ATTENTION:
Units can be pumped down for service
and recharged.
•A servicer can pump down the
refrigerant into the outdoor unit for
maintenance or replacement of
the indoor unit.
•Also the entire system can be
evacuated for maintenance or
replacement of the outdoor unit.

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4.2 Heat Pump Models (DVH):
INDOOR OUTDOOR
LIQUID SIDE
GAS SIDE
HEAT
EXCHANGE
(EVAPORATOR)
HEAT
EXCHANGE
(CONDENSER)
COMPRESSOR
2-WAY VALVE
3-WAY VALVE
CHECK VALVE
(Heating Model only)
CAPILIARY TUBE
REVERSING VALVE
(Heating Model only)
COOLING
HEATING
ACCUMULATOR
ATTENTION:
Units can be pumped down for service
and recharged.
•A servicer can pump down the
refrigerant into the outdoor unit for
maintenance or replacement of
the indoor unit.
•Also the entire system can be
evacuated for maintenance or
replacement of the outdoor unit.

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5.0 Wiring Diagrams:
5.1 Indoor Units:
B-DVC09SD-0, B-DVH09SC-0, B-DVH12SD-0, B-DVH12SD-0
B-DVC18SD-1, B-DVH18SD-1

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B-DVC24SD-1, B-DVH24SD-1

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5.2 Outdoor Units
A-DVC09SD-0, A-DVH09SD-0, A-DVC12SD-0, A-DVH12SD-0
A-DVC18SD-1, A-DVH18SD-1

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6 Installation Details
6.1 Electrical
All electrical wiring must be done according to
local codes. Additionally installations in the
USA, must conform to the current National
Electric Code (NEC) and Installations in
Canada must conform to current Canadian
Electric Code (CEC).
Nameplate data indicates the operating voltage,
phase, ampacity, maximum over current
protection, and minimum voltage.
The contractor is to provide an individual
branch circuit for over current protection for the
unit as required by code. Some codes may
require a disconnect between the indoor and
outdoor unit. Run power supply wiring through
a weatherproof disconnect box and conduit to
the unit connection. Disconnects are required
to be within sight and easy reach of the unit
(usually within 3 feet).
Circuit breakers and disconnect switches
should be properly sized based on the required
codes and the unit’s nameplate requirements.
Check the unit wiring diagram for the number of
conductors required. Ensure that the proper
AWG (gauge) and type of wired is used to
comply with code and the unit’s nameplate.
Route neatly and protect from sharp edges and
damage. Inadequate wiring and/or improper
electrical supply will likely result in failure of the
compressor and other electrical components
and voids the warranty.
6.2 Line Set Connection Sizes
Models
Connection Size
Gas Liquid
DVC09SD-0 / DVH09SD-0 3/8in
(9.52mm)
1/4in
(6.35mm)
DVC12SD-0 / DVH12SD-0
DVC18SD-1 / DVH18SD-1
1/2in
(12.7mm)
1/4in
(6.35mm)
DVC24SD-1 / DVH24SD-1 5/8in
(15.9mm)
3/8in
(9.52mm)
6.3 Line Set Lengths and Elevations
6.4 Field Charging:
Models Max.
Elevation
Max.
Length
DVC/DVH09SD-0 26ft (8m) 66ft
(20m)
DVC/DVH12SD-0
DVC/DVH18SD-1
33ft (10m) 82ft
(25m)
DVC/DVH24SD-1

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7. Operating Conditions
Indoor (Room)
Temperature
Cool Mode Heat Mode Dry Mode
≥62°F(17°C) ≤86°F(30°C) ＞50°F(10°C)
Outdoor (Ambient)
Temperature
5°F - 122°F
(-15°C - 50°C)
5°F - 86°F
(-15°C - 30°C)
32°F - 122°F
(0°C - 50°C)
CAUTION:
1. If the unit is used outside of the above conditions, certain safety protection features may come into
operation and cause the unit to operate abnormally.
2. If the room relative humidity is greater than 80%, the surface of the indoor unit may attract
condensation. To lessen the chance for condensate dripping, set the vertical air flow louver to its maximum
angle (vertically to the floor) and set the fan mode to HIGH.

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8. Electronic Display Functions
8.1 Abbreviations
T1: Indoor room temperature
T2: Coil temperature of evaporator
T3: Coil temperature of condenser
T4: Outdoor ambient temperature
T5: Compressor discharge temperature
Ts: Temperature Set Point
8.2 Display functions
8.2.1 Icon Identification on indoor display board.
Defrost
This indicator illuminates when the
air conditioner starts defrosting
automatically or when the warm air
control feature is activated in
heating mode
Run
Flashes when the unit is in standby.
Illuminates a solid light when the
unit is on.
Timer
This indicator illuminates when
TIMER is set ON/OFF.
Temperature indicator
Displays the temperature settings
when the unit is operational, also
displays any error codes for
diagnosis and troubleshooting.
Signal
Receiver
Receives the signal from the remote
control.
8.3 Main Protection
8.3.1 Compressor Three Minute Time Delay
There is a 1 minute delay the 1st time the unit is
started-up, then a 3 minute delay each time the
unit is started up after the 1st time.
8.3.2 Compressor Top Temperature
Protection
The unit will stop working when the top of the
compressor temperature is reached, and will
restart after the compressor top temperature
protector restarts.
8.3.3 Compressor Discharge Temperature
Protection
When the compressor discharge temperature is
getting high, the frequency of the compressor
will be limited as stated below:
When the compressor discharge temperature
T5>239°F(115°C) for 5s, the compressor will
stop. However, when the temperature is
between 226.4°F (108°C)<T5<239°F (115°C),
the compressor frequency will decrease to the
lowest level every 3 minutes. Then when the
temperature is 194°F (90°C) <T5<221°F
(105°C), the compressor will keep running at
the current frequency. When T5<194°F
(90°C), there will be no limit on the compressor
frequency.
8.3.4 Out of Control Fan Speed
When Indoor Fan Speed runs at 300RPM or
lower, for a designated period of time, the unit
will stop running and the appropriate error code
will show on the display.
8.3.5 Inverter Module Protection
The Inverter module has protection features
regarding current, voltage and temperature. If
these any of these are abnormal, the
corresponding error code will display on indoor
unit and the unit will stop working.
8.3.6 Indoor fan delayed open function
When the unit starts up, the louver will be active
immediately, but the indoor fan will not start for
10s. If the unit is in heating mode, the indoor
fan will be also controlled by anti-cold wind
function to eliminate cold blow.

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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
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≥41°F(5°C).At
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.
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:
27.5
27
High
Low
25
Medium
25.5
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
45
43
40
38
31.5
29.5
22
20
Fmax=F4
Fmax=F7
Fmax=F8
Fmax=F6
Fmax=F3
°F (°C)
81.5 (27.5)
80.6 (27)
77.9 (25.5)
7.7 (25)
°F (°C)
113 (45)
109.4 (43)
104 (40)
118.4 (38)
88.7 (31.5)
85.1 (29.5)
71.6 (22)
68 (20)

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However, if the unit is turned on using the
remote control, the compressor will run at the
Fmax frequency for 7 minutes according to the
outdoor ambient temperature T4. But after 7
minutes, the operation will take into account the
difference (ΔT) in indoor room temperature (T1)
and the Set Point Temperature (Ts) and the
compressor frequency will operate as follows:
3.5
3.0
2.5
2.0
1.5
1.0
0.5
-0.5
-1.0
A
B
C
D
E
F
G
H
The zones (A,B,C...H) shown on the chart
above correspond to the various compressor
running frequencies as a result (ΔT) of the
difference between T1-Ts . When the
temperature differential (ΔT) of T1-Ts remains
in the same zone for 3 minutes, the compressor
will run as follows:
In zones A thru E the ΔT is between 3.5 and 1
Degree, the compressor will continue to
increase the frequency until it reaches its
highest level where Fmax=F8.
In zone F, the compressor continues to run at
its current frequency when the temperature
differential (ΔT) is between 0.5 and 1 degree.
Once the temperature differential (ΔT) falls
below 0.5 degrees, the compressor’s frequency
will decrease unit it reaches the lowest level
where Fmax=F1.
In zone H, where the ΔT is -1 degree or less,
the compressor will run at the lowest frequency
where Fmax=F1 for 1hour.
However, when the temperature differential (ΔT)
is less than -2 degrees, the compressor will
stop.
Additionally, the compressor running frequency
is always limited by the current. Therefore, the
running currents also must be taken into
account. I3COOL, I2COOL, and I1COOL
refer to different running current values in the
table below.
I3COOL
I2COOL
Off
Decrease
Hold
Resume
I1COOL
Indoor units I1COOL
(Amps)
I2COOL
(Amps)
I3COOL
(Amps)
B-DVC09SD-0 13.0 14.0 15.0
B-DVH09SD-0 13.0 14.0 15.0
B-DVC12SD-0 13.0 14.0 15.0
B-DVH12SD-0 13.0 14.0 15.0
B-DVC18SD-1 10.0 11.0 13.0
B-DVH18SD-1 10.5 11.5 13.0
B-DVC24SD-1 12.0 13.0 14.0
B-DVH24SD-1 12.0 13.0 14.0
If the running current is too high (above
I3COOL) in the “Off” zone of the chart above,
the compressor will stop. Between I3COOL
and I2COOL, in the “Decrease” zone the
compressor will lower the frequency to the
lowest level. The “Hold” zone allows the
compressor to continue to run at the current
frequency. Note: When the unit is in “hold”
zone for 3 minutes, the compressor frequency
will rise to the next highest level. This rise in
frequency can occur twice at most while in this
zone. The “Resume” zone places no limitation
on the frequency.
ΔT =T1-Ts
X ΔT°
I