MAXA BDS28A, BDS35A Technical Manual

TECHNICAL MANUAL 2013

SPLIT MONO DC INVERTER

MODELS

BDS28A

BDS35A

This manual has been created for informative purpose. The company declines every responsibility for the results of projecting or installation based on the explanations and the technical specifications given

in this manual. Is besides forbidden the reproduction under any form of the texts and of the figures contained in this manual.

Serie / Series / Serie / Serie

TECHNICAL MANUAL

MONO DC INVERTER

Emissione / Issue Ausgabe / Emission

04 - 2013

Catalogo / Catalogue / Katalog / Catalogue

Sostituise / Supersade Ersetzt / Remplace

MTE01028D2505-00

Index

1. SPECIFICATIONS ......................................................................................................................................4

2. CHARACTERISTICS DATA........................................................................................................................ 6

2.1 Operation characteristic curve .................................................................................................................. 6

2.2 Capacity variation ratio according to temperature .................................................................................... 6

2.3 Noise criteria curve ................................................................................................................................... 6

2.4 Operation data .......................................................................................................................................... 6

3. DIMENSIONS ...........................................................................................................................................7

3.1 Indoor units ............................................................................................................................................... 7

3.2 Outdoor units ............................................................................................................................................7

4. REFRIGERANT DIAGRAM ......................................................................................................................8

5. ELECTRICAL CIRCUIT DIAGRAM ........................................................................................................... 9

5.1 Indoor units ............................................................................................................................................... 9

5.2 Outdoor units ............................................................................................................................................9

6. PRINTED CIRCUIT BOARD.....................................................................................................................10

6.1 Indoor units ............................................................................................................................................. 10

6.2 Outdoor units ..........................................................................................................................................10

7. CONTROL FUNCTIONS .........................................................................................................................11

7.1. Temperature parameters ....................................................................................................................... 11

7.2. Basic functions.......................................................................................................................................11

8. TROUBLESHOOTING ............................................................................................................................15

8.1 Malfunction diagnosis should be performed as below procedure...........................................................15

8.2 Confirmation ...........................................................................................................................................15

8.3 Flashing LED of Indoor/Outdoor unit and primary judgement ................................................................16

8.4. How to check simply the main parts ...................................................................................................... 21

Appendix 1: form for indoor/outdoor unit’s ambient sensor numerical value of resistance ......................... 32

Appendix 2: form for indoor/outdoor unit’s tube temperature sensor numerical value of resistance ..........33

Appendix 3: form for indoor/outdoor unit’s air exhaust temperature sensor numerical value of resistance..34

1. SPECIFICATIONS

Models of indoor units BDS28A BDS35A

Rated voltage 220-240V ~50Hz

Total capacity

Cooling

Heating

Air flow volume (SH/H/MH/M/ML/L/SL) m³/h 730/670/610/530/460/410/380 770/670/610/530/460/410/380

Dehumidifying volume l/h 0,8 1,4

Fan motor cooling speed (Max - Min) r/min 1300/1050/1000/900/800/700/500 1350/1070/1000/900/800/700/500

Fan motor heating speed (Max - Min) r/min 1300/1150/1080/1030/980/900/850 1350/1150/1080/1030/980/900/850

Output of fan motor W 15 15

Fan motor capacitor μF / /

Fan motor RLA A 0,07 0,07

Fan type - piece Cross flow - 1 Cross flow - 1

Diameter x length mm Φ98 x 662 Φ98 x 662

Indoor unit

Evaporator

Swing motor model MP24HA/MP24HB/MP24HC MP24HA/MP24HB/MP24HC

Output of swing motor W 2,4 2,4

Fuse A 3,15 3,15

Sound pressure level dBA 36/32/21 36/32/21

Sound power level dBA 46/42/31 46/42/31

Dimension (W/H/D) mm 866 x 292 x 209 866 x 292 x 209

Dimension of package (W/H/D) mm 945 x 377 x 297 945 x 377 x 297

Net weight/gross weight kg 11/14 11/14

Models of outdoor units BDS28A BDS35A

Compressor manufacturer/trademark SANYO

Compressor model C-6RZ110H1A C-6RZ110H1A

Compressor oil FV50S FVC 68D / RB 68EP

Compressor type ROTARY ROTARY

L.R.A. A 33,00 33,00

Compressor RLA A 4,59 4,59

Compressor power input W 800 800

Overload protector 1NT11L-3979 1NT11L-3979

Throttling method Electronic expansion valve

Starting method 16°C ~ 30°C

Working temperature range (°C) -20°C ~ 48°C

Outdoor unit

Condenser

Fan motor speed rpm 850/750/600 850/750/600

Output fan motor W 40 40

Fan motor RLA A 0,23 0,23

Power input W 520 900

Rated current A 2,3 4,0

S.E.E.R. W/W 7,5-A++ 7-A++

Total capacity

Power input W 565 895

Rated current A 2,37 7,5

S.C.O.P.

Evaporator type Aluminium Fin-copper Tube

Pipe diameter mm Φ7 Φ7

Row-fin gap mm 2-1.5 2-1,5

Coil length x height x width (l x H x L) mm 662 x 25,4 x 305 662 x 25,4 x 305

Condensor type Aluminium Fin-copper Tube

Pipe diameter mm Φ7,94 Φ7,94

Rows-fin gap mm 2,5-1,5 2,5-1,5

Coil length (l) x height (H) x width (L) mm 763 x 57 x 550 730 x 38.1 x 508

kW 2,5(0,7 ~ 4,4) 3,5(0,7 ~ 4,5)

Btu/h 8,53(2,3 ~ 15,00) 11,9(2,3 ~ 15,3)

kW 2,7(0,7 ~ 4,8) 3,5(0,7 ~ 5,5)

Btu/h 9,3(2,4 ~ 16,3) 12,4(2,4 ~ 18,7)

W/W

4,6 – A++ 4,6 – A++

[

]

Fan motor capacitor μF / /

Air flow volume of outdoor unit m³/h 2000 2000

Fan type-piece Axial-flow

Fan diameter mm Φ445 Φ445

Defrosting method Automatic Defrosting

Climate type T1 T1

Isolation I I

Moisture protection IP24 IP24 Permissible excessive operating pressure

for the dischar Permissible excessive operating pressure for the suction side

Sound pressure level dB(A) 49/-/- 50/-/-

Sound power level dB(A) 59/-/- 60/-/-

Dimensions (WXHXD) mm 906 x 596 x 378 906 x 596 x 378

Dimension of package (L/W/H) mm 948 x 420 x 645 348 x 420 x 645

Net weight/gross weight kg 43/47 43/47

Refrigerant charge (R410A) kg 1,3 1,3

Length m 5 5

Gas additional charge g/m 20 20

Outer diameter

Max distance

Connecting pipe

e side

Liquid pipe mm Φ6 Φ6

Gas pipe mm Φ9,52 Φ9,52

Height m 10 10

Length m 15 20

Mpa 3,8 3,8

Mpa 1,2 1,5

The above data of specifications are subject to change without prior notice. Please refer to the actual data specified on the nameplate of

the unit.

Note: Test conditions:

Standard condition

Rated cooling 27 19 35 24

Rated heating 20 15 7 6

3) Microphone at a distance of 1m from the unit.

Approximate calculation from Sound Pressure Level to Sound Power Level:

- Average Sound Pressure Level

: Sound pressure level of front test point.

: Sound pressure level of side test point for indoor unit

- Approximate Sound Power Lever

Dry bulb temp. °C Wet bulb temp. °C Dry bulb temp. °C Wet bulb temp. °C

Indoor side state Outdoor side state

*1.0*1.0

=10*lg

+10.

1010(*2/1

2. CHARACTERISTICS DATA

2.1 Operation characteristic curve

Cooling

Condition Indoor:DB27 Outdoor:DB35 WB24

Indoor air flow: Super High Pipe length: 5m

Current (A)

WB19

BDS35A

BDS28A

Compressor speed (rps)

2.2 Capacity variation ratio according to temperature

200

180

160

140

120

100

Capacity ratio(%)

33 35 37 39 41 43 45

BDS28A

BDS35A

Condition Indoor:DB27 Indoor air flow: Super High Pipe length: 5m

WB19

Outdoor temp.( )

2.3 Noise criteria curve

Noise/dB(A)

Super High

BDS35A

BDS28A

High Middle Low Quiet

Indoor fan motor rotating speed (rps)

2.4 Operation data

Heating

Condition Indoor:DB20 Outdoor:DB7

Indoor air flow:Super High Pipe length: 5m

Current (A)

505151 0 20 30 40 60 70 80 90020304060708090

BDS35A

BDS28A

Compressor speed (rps)

gnitaeHgnilooC

200

180

160

140

120

100

Capacity ratio(%)

40 20

-18 -14 -10 -6 -2 2 6 1

BDS28A

BDS35A

Condition Indoor:DB20 Indoor air flow:Super High Pipe length: 5m

Outdoor temp.( )

tinUroodtuOtinUroodnI

Noise/dB(A)

0 8 20 30 40 50 60 70 80 90

Compressor speed (rps)

BDS35A

BDS28A

Cooling:

Temperature

conditions (°C)

Indoor Outdoor

27/19 35/24

Model

name

BDS28A

BDS35A

Standard

pressure

Heat exchanger pipe

temp.

P(MPa) T1 (°C) T2 (°C)

0,9~1,2

In: 12~14

Out: 10~12

In: 41~43

Out: 43~45

Indoor fan speed

Outdoor fan

speed

Super high Super High

Compressor

revolution (rps)

Heating:

Temperature

conditions (°C)

Indoor Outdoor

20/15 7/6

Model

name

BDS28A

BDS35A

Standard

pressure

P(MPa) T1 (°C) T2 (°C)

2,0~2,6

Heat exchanger pipe

temp.

In: 33~35

Out: 42~44

In: 3~5

Out: 3~5

Indoor fan speed

Super high Super high

Outdoor fan

speed

Notes:

(1) Connecting piping condition: 5m.

(2) T1: Outlet and inlet pipe temperature of evaporator.

T2: Outlet and inlet pipe temperature of condenser.

P: Pressure of air pipe used for connecting outdoor and indoor units.

Notes:

(1) Measure surface temperature of heat exchanger pipe around center of heat exchanger path U bent.

(Thermistor thermometer)

(2) Connecting piping condition: 5m.

3. DIMENSIONS

3.1 Indoor units

866

209

Compressor

revolution (rps)

3.2 Outdoor units

541162 163

4. REFRIGERANT DIAGRAM

TINUROODTUOTINUROODNI

GAS SIDE

HEAT EXCHANGE

(EVAPORATOR)

3-WAY VALVE

LIQUID SIDE

2-WAY VALVE

Discharge

Suction

COMPRESSOR

4-Way valve

Accumlator

Electron expansion valve

HE AT EXCHANGE

(CONDENSER)

reniartSreniartS

COOLING

HEATING

5. ELECTRICAL CIRCUIT DIAGRAM

5.1 Indoor units: BDS28A, BDS35A

FAN

MOTOR

DC-MOTOR

CAP

JUMP

SWING-LR

SWING

ROOM

TEMP.SENSOR

TUBE

TEMP.SENSOR

RT2RT1

ROOM TUBE

AP2

PRINTEDCIRCUITBOAR D

SWING-UD1

SWING

MOTOR(U.D1)MOTOR(L.R)

RECEIVER AND

DISPLAYBOARD

AP1

SWING-UD2

SWING

MOTOR(U.D2)

MAGNETIC

RING

DISP2DISP1

AC-L

COM-OUT

L-OUT

HEALTH-L HEALTH-N

RD BU

COOL PLASMA

GENERATOR

BN(BK) BU(WH)

POWER

YEGN(GN)

BU BK BN

XT1 N(1)

2 3

CONN WIRE

BU BK BN

YEGN

TERMINAL

BOARD

OUTDOOR UNIT

YEGN

EVAPORATOR

YEGN

5.2 Outdoor units: BDS28A, BDS35A

SAT

W3YEGN

W10RD

YEGN

XT2

INDOOR UNIT

N(1)

BK BN

W2BU

W4BK

W1BN

OVC-COMP CN2

COMU AC-L1

OFAN1

FAN

CN1

EKV

TUBE

TEM.SENSOR

RT1

4V AC-L2

RT2

4YV

OUTROOM

TEM.SENSOR

EXHAUST

TEM.SENSOR

RT3

LX-2

W11

L2 L2 L2

W5BU

COMP-U

AP1

LX-1

COMP

W7RD

W6YE

COMP-V COMP-W

W12

W13WH

WHOG

HPP

W8YEGN

HEAT-N2 HEAT-L

(CHASSIS)

N2 N3

EH2

HEATER

W9BU

HEAT-N1

RD RD

EH1

HEATER

(COMP)

6. PRINTED CIRCUIT BOARD

6.1 Indoor unit: BDS28A, BDS35A

12345

6.2 Outdoor units: BDS28A, BDS35A

No Part name

1 DC fan

2 Microswitch

3 Electrostatic precipitation

4 Small up & down swing interface

5 Left and right

Big up & down swing interface

7 Display interface

8 Ambient temperature sensor

9 Tube temperature sensor

Outdoor unit live wire

Input interface of live wire for

indoor unit

Health

Fuse

Interface of neutral wire for

indoor and outdoor units

Communication interface of

8911 1012

indoor and outdoor units

No Part name

1 Input of neutral wire of power

2 Input of live wire of power

Communication interface

Interface 1 of electric reactor

Interface 2 of electric reactor

6 Interface of fan

Neutral wire of electric heater of

chassis

Neutral electric wire of

compressor

9 Neutral wire of 4-way valve

Live wire of 4-way valve

Live wire of electric heater

Input of overload

Temperature sensor

U, V, W three phases of

compressor

15 Input of ground wire of power

7. Control functions

7.1. Temperature Parameters

• Indoor preset temperature (Tpreset)

• Indoor ambient temperature (T

amb)

7.2. Basic functions

Once energized, the compressor should in no way be restarted unless after at least 3-minute time interval. In case of having

memory function, for the first energization, the compressor will be started without 3-minute lag, if being under the condition

of power-off, and the compressor will have 3-minutes delay to be started under the condition of power-on. Once started, the

compressor will not be stopped within 6 minutes with the changes of room temperature.

7.2.1 Cooling Mode

 Cooling Condition and Process

When T

and the indoor fan will run at preset speed.

When T

at preset speed.

When T

■ Under this mode, the switchover (reversal) valve will be de-energized and the temperature can be set from 16°C to 30°C.

If the compressor is shut down for some reason, the indoor fan and the swing device will operate at the original state.

amb. ≥ Tpreset , the unit will run under cooling mode, in which case the compressor and outdoor fan will be started,

amb. ≤ Tpreset -3°C, the compressor will stop, the outdoor fan will stop with time lag of 30s, and the indoor fan will run

preset -3°C <Tamb. < Tpreset , the unit will maintain its original operating status.

Tpreset

Tpreset –2 ˚C

Tamb.

≥ 6 min. ≥ 3 min. ≥ 6 min.

Start cooling

Original operating status

Stop cooling

Compressor

Outdoor fan

Indoor fan

Run

Setting fan speed

Stop

 Protection function

♦ Overcurrent protection

If total current is high, the compressor will run in limited frequency. If total current is too high, the compressor will stop, the

outdoor fan will delay 30 seconds to stop, indoor unit will display E5 and outdoor yellow light will blink 5 times.

♦ Antifreeze protection

When the antifreeze protection is detected, the compressor will stop, the outdoor fan will stop after 30 seconds, and the

indoor fan and swing motor will keep running in the original mode. When antifreeze protection is eliminated and the compressor has stopped for 3 minutes, the compressor will resume running in the original mode.

The period ofantifreezing protection

Compressor

3 min

Outdoor fan

Indoor fan

Low fan speed

Run

Stop

7.2.2 Dehumidifying mode

7.2.2.1 The condition and process of dehumidifying

If T

amb. > Tpreset, DRY mode will act, the indoor fan, outdoor fan and compressor will run, and indoor fan will run at low

speed.

set - 2°C ≤ Tambient ≤ Tpreset, the unit will keep running in the original mode.

If T

am. ≤ Tset - 2°C, the compressor will stop running, the outdoor fan will delay 30 seconds to stop and the indoor fan will

If T

run at low speed.

7.2.2.2 Protection function

Protection is the same as that under COOL mode.

7.2.3 HEAT mode

7.2.3.1 The condition and process of heating

If T

amb ≤ Tprset + 2°C, HEAT mode will act, the compressor, outdoor fan and reversal valve will run, the indoor fan will delay

3min to stop at the latest.

prset +2°C < Tamb < Tprset + 5°C, the unit will keep running in the original mode.

If T

amb > Tprset + 5°C, the compressor will stop, the outdoor fan will delay 30 sec to stop and Indoor unit fan blow with low

If T

speed for 60s,during this period, fan speed is not changeable.

● In this mode, the temperature setting range is 16°C ~ 30°C.

The air conditioner will adjust the running frequency of the compressor automatically according to the change of ambient

temperature.

● When the unit is turned off in HEAT mode, or switched to other mode from HEAT mode, the four –way valve will be

powered off after the compressor stops.

Stop heating

Original running state

Compressor

Outdoor Unit

Indoor Unit

Reversal valve

amb

6min 3min 6min

30s 30s

Set fan speed

3min

Run

60s

3min

Stop

Start heating

60s

7.2.3.2 The condition and process of defrosting

When frost is detected in the condenser, the system will enter into defrosting state. When defrosting starts, the compressor

and indoor fan will stop, and the outdoor fan and four-way valve will delay 30 seconds to stop. The compressor will start

after 15 seconds and then defrosting will be started. When the compressor has run for 7 minutes or defrosting is finished,

the compressor will stop. After 30 seconds the four – way valve opens and after an other 60 seconds, the compressor and

outdoor fan resume running. The indoor fan will delay 3 minutes to run at the la test and temperature on the display panel

shows H1.

The period of defrosting

Four-way valve

7min

Compressor

Outdoor Unit

Indoor Unit

Run Stop

3min

Set fan speed

7.2.3.3 Protection function

♦ Anti-cold – wind protection

In HEAT mode, in order to prevent the indoor unit from blowing out cold wind, each time the compressor starts, the indoor

fan will delay 3 minutes after the compressor to run at the latest and it can adjust fan speed automatically when

temperature is low.

♦ Overcurrent protection

Overcurrent protection is the same with that in COOL mode.

 Protection

♦ Cold air prevention

The unit is started under heating mode (the compressor is ON):

① In the case of T

speed with a time lag of 2 minutes. Within 2 minutes, if T

indoor amb. < 24°C: if Ttube ≤ 40°C and the indoor fan is at stop state, the indoor fan will begin to run at low

tube > 40°C, the indoor fan also will run at low speed; and after

1-minute operation at low speed, the indoor fan will be converted to operation at preset speed. Within 1-minute low speed

operation or 2-minute non-operation, if T

② In the case of T

indoor amb. ≥ 24°C: if Ttube > 42°C, the indoor fan will run at low speed, and after one minute, the indoor fan

will be converted to preset speed. Within one-minute low speed operation, if T

tube > 42°C, the fan will run at present speed.

tube > 42°C, the indoor fan will be converted to

preset speed.

Note: T

indoor amb. indicated in ① and ② refers to, under initially heating mode, the indoor ambient temperature before the

command to start the compressor is performed according to the program, or after the unit is withdrawn from defrost, the

indoor ambient temperature before the defrost symbol is cleared.

♦ Total current up and frequency down protection

If the total current I

compressor will run at reduced frequency; and if I

total ≤ W, frequency rise will be allowed; if Itotal ≥ X, frequency rise will not be allowed; if Itotal ≥ Y, the

total ≥ Z, the compressor will stop and the outdoor fan will stop with a time

lag of 30s.

7.2.4 Fan Mode

Under the mode, the indoor fan will run at preset speed and the compressor, the outdoor fan, the four-way valve and the

electric heater will stop.

7.2.5 AUTO Mode

① Working conditions and process of AUTO mode

Under AUTO mode, standard cooling temperature T

a) Once energized, if T

amb. ≤ 22°C, the unit will be started under heating mode; if 23°C< Tamb.< 25°C, the unit will run under

fan mode and the run indicator will be bright; and if T

b) Under AUTO mode, if T

temperature is 25°C; if T

the indoor fan will run at set speed; and if T

c) Under AUTO mode, if T

preset temperature is 20°C; if T

amb. ≥ Tset is detected, the unit will select to run under cooling mode, in which case implicit set

amb. ≤ Tpreset - 2°C, the compressor will stop, the outdoor fan will stop with a time lag of 1 minute, and

set - 2°C< Tamb.< Tset, the unit will remain at its original state.

amb. ≤ Tset+2°C is detected, the unit will select to run under heating mode, in which case implicit

amb. ≥ Tset + 5°C, the compressor will stop, the outdoor fan will stop with a time lag of 1

set is 25°C and standard heating temperature Tset is 20°C.

amb. ≥ 25°C, the unit will be started under cooling mode.

minute, and the indoor fan will run under the mode of residue heat blowing; and if T

remain at its original state.

d) Under AUTO mode, if 23°C < T

amb.< 25°C, the unit will remain at its original state.

set +2°C< Tamb.< Tset + 5°C, the unit will

② Protection

a) In cooling operation, protection is the same as that under the cooling mode;

b) In heating operation, protection is the same as that under the heating mode;

c) When ambient temperature changes, operation mode will be converted preferentially. Once started, the compressor will

remain unchanged for at least 6 minutes.

7.2.6 Common Protection Functions and Fault Display under COOL, HEAT, DRY and AUTO Modes

① Overload protection

tube: measured temperature of outdoor heat exchanger under cooling mode; and measured temperature of indoor heat

exchanger under heating mode.

1) Cooling overload

tube ≤ 52°C, the unit will return to its original operation state.

a) If T

b) If T

tube ≥ 55°C, frequency rise is not allowed.

tube ≥ 58°C, the compressor will run at reduced frequency.

c) If T

tube ≥ 62 °C, the compressor will stop and the indoor fan will run at preset speed.

d) If T

2) Heating overload

a) If T

tube ≤ 50°C, the unit will return to its original operation state.

b) If T

tube ≥ 53°C, frequency rise is not allowed.

tube ≥ 56°C, the compressor will run at reduced frequency.

c) If T

tube ≥ 60°C, the compressor will stop and the indoor fan will blow residue heat and then stop.

d) If T

② Exhaust temperature protection of compressor

If exhaust temperature ≥98°C, frequency is not allowed to rise.

If exhaust temperature ≥103°C, the compressor will run at reduced frequency.

If exhaust temperature ≥110°C, the compressor will stop.

If exhaust temperature ≤90°C and the compressor has stayed at stop for at least 3 minutes, the compressor will resume its

operation.

③ Communication fault

If the unit fails to receive correct signals for durative 3 minutes, communication fault can be justified and the whole system

will stop and the display will show the error code E6.

④ Module protection

Under module protection mode, the compressor will stop. When the compressor remains at stop for at least 3 minutes, the

compressor will resume its operation. If module protection occurs six times in succession, the compressor will not be started

again.

⑤ Overload protection

If temperature sensed by the overload sensor is over 115°C, the compressor will stop and the outdoor fan will stop with a

time lag of 30 seconds. If temperature is below 95°C, the overload protection will be relieved.

⑥ If voltage on the DC bus is below 150V or over 420V

If voltage on the DC bus is below 150V or over 420V, the compressor will stop and the outdoor fan will stop with a time lag of

30 seconds. When voltage on the DC bus returns to its normal value and the compressor has stayed at stop for at least 3

minutes, the compressor will resume its operation.

⑦ Faults of temperature sensors

Designation of sensors Faults

Indoor ambient temperature The sensor is detected to be open-circuited or short-circuited for successive 30 seconds. Indoor tube temperature The sensor is detected to be open-circuited or short-circuited for successive 30 seconds. Outdoor ambient temperature The sensor is detected to be open-circuited or short-circuited for successive 30 seconds.

Outdoor tube temperature

Exhaust

Overload

The sensor is detected to be open-circuited or short-circuited for successive 30 seconds, and no detection is performed within 10 minutes after defrost begins. After the compressor has operated for 3 minutes, the sensor is detected to be open-circuited or short-circuited for successive 30 seconds. After the compressor has operated for 3 minutes, the sensor is detected to be open-circuited or short-circuited for successive 30 seconds.

8 Power-failure memory protection

Memory content: mode, up-down purging, lighting, set temperature, and set fan speed. After having power failure, it can

automatically start operating according to the memory content after being powered on again. If no timing function is set in the

final remote control order, the system will memorize the latest remote control order and then operate based on the manner

set during the latest time. There is common timing function included in the latest remote control order. If the system has

power failure when the timed time is still not reached, the system will memorize the timing function in the latest remote

control order after being powered on again, and the timing time will be calculated from the power-on time again. If there is

timing function in the latest remote control order, when the timed time is reached and there is power-failure after the system

conduct the action of the set timed start or timed stop, then after powered on again, the system will memorize the operating

condition before power failure and will not implement the timing action, and also the moment timing will not be memorized.

8. TROUBLESHOOTING

8.1 Malfunction diagnosis should be performed as below procedure

Step Malfunction diagnosis procedure

1 Conform malfunction

2 Read out the error code for indoor/outdoor unit and then find out the corresponding malfunction name

3 Troubleshooting and maintenance (refer to the content as below for details)

Note: There’s high capacity electrolytic capacitor on outdoor unit’s main board. Therefore, there’s still high voltage (DC

280V-380V, which is depending on the input voltage) in the capacitor even if the power is disconnected.

That voltage can only be decreased to the safety valve after more than 20mins. There will be electric shock if you touch the

electrolytic capacitor within 20mins. Therefore, if it needs to maintain it after disconnecting the power, you must discharge

the electrolytic capacitor according to below method.

8.2 Confirmation

(1) Confirmation of Power Supply

Confirm that the power breaker operates (ON) normally;

(2) Confirmation of Power Voltage

Confirm that power voltage is AC 220–230–240 ±10%. If power voltage is not in this range, the unit may not operate

normally.

8.3 Flashing LED of Indoor/Outdoor unit and primary judgement

No Malfunction

High pressure

protection of system

Antifreezing

protection

Refrigerant

leakage protection

High discharge Temperature

protection of compressor

Overcurrent

protection

Communication

Malfunction

High temp.

resistant protection

EEPROM

malfunction

Limit/decrease frequency due

to high temp of module

Display Method of Indoor Unit

Indicator Display (during

blinking, ON 0.5s and OFF

LED

Operation Indicator

Blinks

once

Blinks

twice

Blinks 4

times

Blinks 5

times

Blinks 6

times

Blinks 8

times

0.5s)

COOL

Indicator

Blinks 6 times

Heating

Indicator

Blinks 15 times

Blinks 6 times

Display Method of Outdoor Unit Indicator has 3 kinds of display

status and they will be displayed

circularly every 5s.

Yellow

Indicator

Red

Indicator

Blinks 3 times

Blinks 7 times

Blinks 5

times

Always

Blinks 6 times

Blinks 11 times

Blinks 9 times

Green

Indicator

A/C status Possible causes

- During cooling and drying operation, except indoor fan operates, all loads stop operation.

- During heating operation, the complete unit stops.

During cooling and drying operation, compressor and outdoor fan stop while indoor fan operates.

The Dual-8 Code Display will show F0 and the complete unit stops.

- During cooling and drying operation, compressor and outdoor fan stop while indoor fan operates.

- During heating operation, all loads stop.

- During cooling and drying operation, compressor and outdoor fan stop while indoor fan operates.

- During heating operation, all loads stop.

- During cooling operation, compressor stops while indoor fan motor operates.

- During heating operation, the complete unit stops.

- During cooling operation: compressor will stop while indoor fan will operate.

- During heating operation, the complete unit stops.

- During cooling and drying operation, compressor will stop while indoor fan will operate.

- During heating operation, the complete unit will stop

All loads operate normally, while operation frequency fo compressor is decreased

1. Refrigerant was superabundant.

2. Poor heat exchange (including filth blockage of heat exchanger and bad radiating environment);

3. Ambient temperature is too high.

1. Poor air-return in indoor unit.

2. Fan speed is abnormal.

3. Evaporator is dirty.

1. Refrigerant leakage;

2. Indoor evaporator temperature sensor works abnormally;

3. The unit has been plugged up somewhere

Please refer to the malfunction analysis (discharge protection, overload).

1. Supply voltage is unstable.

2. Supply voltage is too low and load is too high.

3. Current is too high.

Refer to the corresponding malfunction analysis.

Refer to the malfunction analysis (overload, high temperature resistant).

Replace outdoor control panel AP1.

Discharging after the complete unit is de-energized for 20min, check whether the thermal grease on IPM Module of outdoor control panel AP1 is sufficient and whether the radiator is inserted tightly. If it’s no use, please replace control panel AP1.

Malfunction protection of

jumper cap

Gathering

refrigerant

Indoor ambient temperature

sensor is open/short circuited

Indoor evaporator temperature

sensor is open/short circuited

Outdoor ambient temperature

sensor is open/short circuited

Outdoor condenser temperature

sensor is open/short circuited

Outdoor discharge temperature

sensor is open/short circuited

Limit/decrease frequency due

to overload

Decrease frequency due

to overcurrent

Blinks 15 times

Blinks 1 time

Blinks once

Blinks twice

Blinks 3 times

Blinks 4 times

Blinks 5 times

Blinks 6 times

Blinks 8 times

Blinks 17

time

Blinks 6 times

Blinks 5 times

Blinks 7 times

Blinks 3

times

Blinks

once

Wireless remote receiver and button are effective, but can not dispose the related command

When the outdoor unit receive signal of Gathering refrigerant, the system will be forced to run under cooling mode for gathering refrigerant

- During cooling and drying operation, indoor unit operates while other loads will stop.

- During heating operation, the complete unit will stop operation.

- During cooling and drying operation, indoor unit will operate while other loads will stop;

- During heating operation, the complete unit will stop operation.

- During cooling and drying operating, compressor stops while indoor fan operates;

- During heating operation, the complete unit will stop operation

- During cooling and drying operation, compressor stops while indoor fan will operate;

- During heating operation, the complete unit will stop operation.

- During cooling and drying operation, compressor will sop after operating for about 3 minutes, while indoor fan will operate;

- During heating operation, the complete unit will stop after operating for about 3 minutes. All loads operate normally, while operation frequency for compressor is decreased All loads operate normally, while operation frequency for compressor is decreased

1. No jumper cap insert on mainboard.

2. Incorrect insert of jumper cap.

3. Jumper cap damaged.

4. Abnormal detecting circuit of mainboard.

Nominal cooling mode

1. Indoor ambient temperature sensor hasn’t been connected well with indoor unit’s control panel AP1 (refer to the wiring diagram for indoor unit).

2. Room temperature sensor is damaged (refer to the resistance table of temp. sensor appendix 1) 3 Mainboard damaged

1. Evaporator temp. sensor hasn’t been connected well with indoor unit’s control panel AP1 (refer to the wiring diagram for indoor unit).

2. Evaporator temp. sensor is damaged (please refer to the resistance table of temp. sensor).

1. Outdoor ambient temp. sensor hasn’t been connected well or is damaged.

2. Please check it by referring to the resistance table for temperature sensor appendix 1).

1. Condenser temp. sensor hasn’t been connected well or is damaged.

2. Please check it by referring to the resistance table for temperature sensor appendix 2)

1. Outdoor discharge temp. sensor hasn’t been connected well or is damaged. Please check it by referring to the resistance table for temp. sensor appendix 3).

2. The head of temp. sensor hasn’t been inserted into the copper tube. Refer to the malfunction analysis (overload, high temperature resistant).

The input supply voltage is too low; System pressure is too high and overload.

Decrease frequency due

to high air discharge

Limit/decrease frequency due

to antifreezing

DC generatrix

voltage is too high

Voltage of DC

bus-bar is too low

Compressor Min frequence

in test state Compressor rated frequence

in test state Compressor

Max frequence

in test state Compressor

intermediate

frequence in test state

Overcurrent protection of

phase current for compressor

Charging malfunction of

capacitor

Malfunction of module temp.

sensor circuit

1. Overload or

All loads operate normally, while operation frequency for compressor is decreased

During cooling, dehumidifying, compressor stop running fan motor works. During heating: all will stop

- During cooling and drying operation, compressor will stop while indoor fan will operate.

- During heating operation, the complete unit will stop.

During cooling and drying operation, compressor will stop while indoor fan will operate; During heating operation, the complet unit will stop operation.

- During cooling and drying operation, compressor will stop while indoor fan will operate.

- During heating operation, the complet unit will stop.

- During cooling and drying operation, compressor will stop while indoor fan will operate;

- During heating operation, the complet unit will stop

Blinks

twice

Blinks 4

times

Blinks 9 times

Blinks 2 times

Blinks 11 times

Blinks

0.25Hz

Blinks

0.25Hz

Blinks

0.25Hz

Blinks

0.25Hz

Blinks

0.25Hz

Blinks 2 times

Blinks 21 times

Blinks

0.25Hz

Blinks

0.25Hz

Blinks

0.25Hz

Blinks

0.25Hz

Blinks

0.25Hz

Blinks 17 times

Blinks 18 times

Blinks 13 times

Blinks 12

times

temperature is too high.

2. Refrigerant is insufficient;

3. Malfunction of electric expansion valve (EXV.

Poor air-return in indoor unit or fan speed is too low

1. Testing the voltage of position L and N on terminal XT, if higher than 265VAC, please cut off the power supply and restart until back to normal.

2. If input voltage is normal, testing the voltage of electrolytic capacitor C on AP1 after turn on the unit. There may be some problem and replace the AP1 if the electrolytic capacitor voltage range at 200-280V.

1. Measure the voltage of position L and N on wiring board (XT), if the voltage is higher than 150VAC, turn on the unit after the supply voltage is increased to the normal range.

2. If the AC input is normal, measure the voltage of electrolytic capacitor C on control panel (AP1), if it’s normal, there’s malfunction for the circuit, please replace

the control panel (AP1) Showing during min. cooling or min. heating test Showing during nominal cooling or nominal heating test Showing during max. cooling or max. heating test

Showing during

middle cooling or

middle heating test

Refer to the

malfunction analysis

(IPM protection, loss

of synchronism

protection and

overcurrent protection

of phase current for

compressor.

Refer to the part

three—charging

malfunction analysis

of capacitor.

Replace outdoor

control panel AP1

Module high

temperature

protection

Decrease frequency due to high temp.

resistant during heating operation Static dedusting

protection

Overload

protection for compressor

System is

abnormal

35 IPM protection H5

Module temp.

is too high

Internal motor (fan motor) do

not operate

Desynchronizing

of compressor

39 PFC protection HC

Outdoor DC fan motor

malfunction

Power

protection

Blinks 11

times

Blinks 23

times

Blinks 20

times

Blinks 19 times

Blinks 10 times

Blinks twice

Blinks 3 times

Blinks 4 times

Blinks 5 times

Blinks 7 times

Blinks 6 times

Blinks 8 times

Blinks 6 times

Blinks 4 times

Blinks 10 times

Blinks 14 times

Blinks 9 times

Blinks 14 times

After the complete

During cooling operation, compressor will stop while indoor fan will operate; During heating operation, the complete unit will stop

All loads operate normally, while operation frequency for compressor is decreased

- During cooling and drying operation, compressor will stop while indoor fan will operate;

- During heating operation, the complete unit will stop operation.

- During cooling and drying operation, compressor will stop while indoor fan will operate;

- During heating operation, the complete unit will stop operation.

- During cooling and drying operation, compressor will stop while indoor fan will operate;

- During heating operation, the complete unit will stop operation

Internal fan motor, external fan motor, compressor and electric heater stop operation, guide louver stops at present location.

During cooling and drying operation, compressor will stop while indoor fan will operate; During heating operation, the complet unit will stop operation.

- During cooling and drying operation, compressor will stop while indoor fan will operate;

- During heating operation, the unit will stop operation Outdoor DC fan

motor malfunction lead to compressor stop operation, compressor stop operation and outdoor fan motor will stop 30s latter, 3 minutes latter fan motor and compressor will restart

unit is deenergized for

20mins, check

whether the thermal

grease on IPM

Module of outdoor

control panel AP1 is

sufficient and whether

the radiator is inserted

tightly. If it’s no use,

please replace control

panel AP1.

Refer to the

malfunction analysis

(overload, high

temperature resistant)

1. Wiring terminal

OVC-COMP is

loosened. In normal

state, the resistance

for this terminal should

be less than 1ohm.

2. Refer to the

malfunction analysis

(discharge protection,

overload)

Refer to the

malfunction analysis

(overload, high

temperature resistant)

Refer to the

malfunction analysis

(IPM protection, loss

of synchronism

protection and

overcurrent protection

of phase current for

compressor.

1. Bad contact of DC

motor feedback

terminal.

2. Bad contact of DC

motor control end.

3. Fan motor is

stalling.

4. Motor malfunction.

5. Malfunction of

mainboard rev

detecting circuit.

Refer to the

malfunction analysis

(IPM protection, loss

of synchronism

protection and

overcurrent protection

of phase current for

compressor.

Refer to the

malfunction analysis.

DC fan motor

malfunction or system

blocked or the

connector loosed

To protect the

electronical

components when

detect high power

Indoor unit and outdoor unit

does not match

Failure

start-up

Malfunction of phase current detection

circuit for compressor

Malfunction of voltage

dropping for DC bus-bar

Malfunction of

complete unit’s current detection

The four-way valve is

abnormal

Zerocrossing malfunction of

outdoor unit

Blinks 19

times

Blinks 11 times

Blinks 13 times

Blinks 20 times

Blinks 13 times

Blinks 20 times

Blinks 18 times

Blinks 16

times

compressor and outdoor fan motor can’t work

- During cooling and drying operation, compressor will stop while indoor fan will operate.

- During heating operation, the complete unit will stop operation.

- During cooling and drying operation, compressor will stop while indoor fan will operate;

- During heating operation, the complet unit will stop

- During cooling and drying operation, compressor will stop while indoor fan will operate;

- During heating operation, the complet unit will stop.

- During cooling and drying operation, the compressor will stop while indoor fan will operate;

- During heating operating, the complete unit will stop operation.

If this malfunction occurs during heating operation, the complet unit will stop operation.

During cooling operation, compressor will stop while indoor fan will operate; during heating, the complete unit will stop operation.

Indoor unit and

outdoor unit doesn't

match

Refer to the

malfunction analysis.

Replace outdoor

control panel.

Supply voltage is

unstable.

There’s circuit

malfunction on

outdoor unit’s control

panel AP1, please

replace the outdoor

unit’s control panel

AP1.

1. Supply voltage is

lower than AC175V;

2. Wiring terminal 4V

is loosened or broken;

3.4V is damaged,

please replace 4V.

Replace outdoor

control panel AP1

Frequency

limiting(power)

Compressor

running

The temp. for turning on the

unit is reached

Frequency limiting(module

temperature)

Normal

comunication

54 Defrosting

Blinks once (during blinking, ON 10s and OFF

0.5s)

Blinks

once

Blinks

twice

Blinks 13 times

Blinks 8 times

Blinks 11 times

Blinks

once

- Defrosting will occur in heating mode. Compressor will operate while indoor fan will stop operation.

It’s the normal state.

8.4. How to check simply the main part

8.4.1 Indoor Unit:

8.4.1.1 Temperature sensor malfunction (F1/F2)

F1 and F2 malfunction

Is the wiring terminal between temp. sensor and the controller loosened or poorly contacted?

Yes

Is there short circuit due to trip over of the parts?

Is the temperature sensor normal according to the resistance table?

Insert the temperature sensor tightly

Malfunction is eliminated

Yes

Make the parts upright

Yes

Malfunction is eliminated

Replace it with a temp. sensor with the same model

Replace the main board with the same model

Yes

Malfunction is eliminated

Yes

End

8.4.1.2 Indoor fan does not operate (H6 Malfunction) Possible causes:

1. Fan motor is locked;

2. The feedback terminal of PG motor is not connected tightly;

3. The control terminal of PG motor is not connected tightly;

4. Motor is damaged;

5. Malfunction of the rotation speed detection circuit of the mainboard.

See the flow chart below:

“H6” is displayed on the unit.

Stir the fan blade with a hand when the unit is DE-ENERGIZED.

Does the blade rotate smoothly?

Reinstall the motor and the blade to make it rotate smoothly.

Yes

Is the malfunction eliminated?

Is the wiring terminal of PG motor loose?

Yes

Insert the wiring terminal of indoor fan

Is the malfunction eliminated?

Energize and retart up the unit, test if the voltage between motor terminal 1 and 2 is 280 ~ 310VDC

Yes

It’s the malfunction of the main

board. Replace the main board with the same model

Is the malfunction eliminated?

Test if the voltage between motor terminal 2 and 3 is 15VDC

It’s the malfunction of the main board. Replace the main board with the same model

Yes

Is the malfunction eliminated?

It’s the malfunction of the motor. Replace the motor

Yes

End

8.4.1.3. Jumper cap malfunction (C5) Possible causes:

1. There is no jumper cap on the controller;

2. Jumper cap is not inserted properly and tightly;

3. Jumper cap is damaged;

4. Controller is damaged. See the flow chart below:

C5 is displayed on the unit.

Is there jumper cap on the mainbaord? Install a matching jumper cap.

Yes

Is the jumper cap inserted incorrectly or improperly?

Replace the jumper cap

Is the malfunction eliminated?

The mainboard is defined abnormal; replace it

End

Is the malfunction eliminated?

Yes

Re-insert the jumper cap.

Is the malfunction eliminated?

Yes

8.4.1.4 Communication Malfunction (E6)

1. Check if connection wire between indoor and outdoor units and wire inside the unit are connected well.

2. Check if mainboard of indoor or outdoor unit is damaged.

Communication malfunction of indoor unit

Power off the unit and check if the connecting wire of indoor and outdoor unit and wiring o electric box are correct.

Is wire connected correctly?

Connect wires according to the wiring diagram

Power off the unit. Change the communication cable o indoor units. Energize the unit and wait for 3 min

Yes

Does the broken-down indoor unit resume normal?

Yes

Replace mainboard of outdoor unit

Replace the broken-down mainboard of the indoor unit

Yes

Is malfunction removed？

End

8.4.2 Outdoor Unit:

8.4.2.1 Key detection points

Test5

Test3

Test2

Test4

Test1

Test6

Test point SN Test point Related specification Test value in normal condition

Test 1 Between AC-L1 and N1 Neutral and live wire 165V ~ 253V

Test 2 Left side of R201, radiator U404 DC bus bar 230V ~ 380V

Test 3 Top of D304, Bottom of D304 IPM drive voltage + 15V 13,5V ~ 15,5V

Test 4 Top of C116, bottom of C116 Relay drive voltage +12V 11V ~ 13V

Test 5 Right side of R228, left side of D228 PFC drive voltage +15V 13,5V ~ 15,5V

Test 6 Left and top ends of U4, bottom of U4 Chip +3,3V 3,1V ~ 3,3V

Test 7 Right and top end of U4, bottom of U4 +5V 4,8V ~ 5,1V

Test 8 Bottom of R506, bottom of U4 Outdoor unit receiving signal Fluctuate between 0 and 3,3V

Test 9 Bottom of R523, bottom of U4 Outdoor unit sending signal Fluctuate between 0 and 3,3V

Test7

Test8 Test9

8.4.2.2. Capacitor charging malfunction (Fault with outdoor unit) (AP1 below refers to the outdoor control panel)

Main detection point:

• Use AC voltmeter to check if the voltage between terminal L and N on the wiring board is within 210VAC ~ 240VAC.

• If the reactor (L) is correctly connected? If the connection is loose or fallen? If the reactor (L) is damaged?

Fault diagnosis proess:

Switch on the unit and wait 1 minute.

Use DC voltmeter to measure the voltage on the two ends of electrolytic capacitor.

Voltage higher than 200V Faulty with the voltage testing

Yes

circuit on control panel AP1

Replace the control panel AP1

Measure the AC voltage between terminal L and N on wiring board XT(power supply)

Voltage within 210 ~ 250VAC.

Yes

Switch off the power and wait 20 minutes; or use DC voltmeter to measure the voltage on the two ends of capacitor (test3), until the voltage is lower than 20V.

Check the connection of reactor (L in the Electrical Wiring Diagram)

If the wiring of reactor L is normal?

Replace the control panel AP1

Yes

Switch off the power and repair

the supply power to restore the voltage to 210VAC ~ 250 VAC

Connect the reactor L according to Electrical Wiring Diagram

Re-energize and switch on the unit

If the fault is elmininated?

If the fault is eliminated

Yes

8.4.2.3 IPM Protection, desynchronizing malfunction, Compressor Phase Overcurrent (AP1 below refers to the

outdoor control panel)

Main detection point:

• If the connection between control panel AP1 and compressor COMP is secure? If loose? If the connections are correct?

• If the voltage input of the machine is within normal range? (use AC voltmeter to measure the voltage between terminal L

and N on the wiring board XT)

• If the compressor coil resistance is normal? If the insulation of compressor coil’s against the copper tube is in good

condition?

• If the working loads of the machine are too hight? If the radiation is good?

• If the charge volume of refrigerant is correct?

Fault diagnosis process:

Energize and switch on

IPM Protection occurs after the machine has run for a periode of time?

Yes

Use AC voltmeter to measure the voltage between terminal L and N on the wiring board XT

If the voltage between terminal L and N on wiring board XT is within 210VAC 250VAC?

Yes

Please confirm:

1. In the indoor and outdoor heat exchangers are obstructed by other objects which affect the heat exchange of indoor and outdoor unit.

2. If the indoor and outdoor fans are working normally?

3. If the environment temperature is too high and exceeds the permissible range?

4. If the charge volume of refrigerant is too much, resulting in that the system the system pressure is too high?

5. Other conditions resulting in that the system pressure is becomes too high.

Voltage between the two ends of electrolytic capacitor (tes3) is higher than 250V.

Stop the unit and disconnect the power supply. Then, check the connection of capacitor C2 according to wiring diagram.

Remove the wires on the two ends of capacitor C2, then use capacitance meter to measure the capacitor C2. Verify as per the parameters sheet (spec).

Refer to the electrical wiring diagram and check if the connection between AP1 and COMP is loose and if the connection order is correct.

If the connection between AP1 and COMP is unsecure or the connection order is wrong?

Use ohmmeter to measure the resistance between the three terminals on compressor COMP, and compare the measurments with the compressor resistance on servuice manual

Use ohmmeter to measure the resistance between the two terminals of compressor COMP and copper tube.

If capacitor C2 is failled?

Connect the control panel AP1 and compressor COMP correctly according to the electrical wiring diagram. Then, energize and start the unit.

If the resistance is normal?

Resistance higher than 500MΩ?

Start and run the unit. Before protection occurs, use DC voltmeter to measure the voltage between the two ends of electrolytic capacitor on control panel AP1.

The connection of capacitor C2 is loose

Stop the unit and disconnect the power supply. Wait 20 minutes or use DC voltmeter to measure the voltage between the two ends of capacitor C2, until the voltage is lower than 20V

Replace the capacitor C2. Then, energize and start the unit

Replace the control panel AP1

The corrective actions according to Technical Service Manual, and then energize and start the unit.

Replace the control panel AP1.

Replace the compressor COMP

Replace the control panel AP1

End

Reconnect the capacitor C2 according to electrical wiring diagram, then energize and start the unit.

If the unit can work normally.

Check the supply voltage and restore it to 210VAC 250VAC

If the unit can work normall?

If the unit can work normally?

If the unit can work normally

Yes

8.4.2.4. High temperature and overload protection diagnosis (AP1 herinafter refers to control board of the outdoor unit)

Main detection point:

● Is outdoor ambient temperature in normal range?

● Are the outdoor and indoor fans operating normally?

● Is the heat dissipation environment inside and ouside the unit is good?

Overheat and high temperature protection

Is outdoor ambient temperature higher than 53°C?

Normal protection, please operate it after the outdoor ambient temp. is normalized.

20 minutes after the complete unit is powerd off

Is heat dissipation of the indoor unit and outdoor unit abnormal?

Does the outdoor fan work normally

Replace the control panel AP1

End

8.4.2.5. Start up failure (following AP1 for outdoor unit control board)

Main detection point:

● Whether the compressor wiring is connected correct?

● Is time for compressor stopping enough?

● Is compressor broken?

● Is the refrigerant charging is too much?

Improve the heat dissipation environment of the unit

1. Check if the fan terminal OFAN is connected correctly.

2. Resistance between any ohm gauge and should be less than 1kΩ.

Replace the fan capacitor C1

Replace the outdoor fan

Power on the unit

Is stop time of the compressor longer than 3 minutes

Restart it up after 3 minutes?

Does the start up fail?

Are the wires for the compressor connected correctly? Is connection sequence right?

Connect the wires as per the connection diagram.

Replace the control panel AP1

If the fault is eliminated?

Replace the compressor

End

8.4.2.6 Diagnosis for compressor Out of step (synchronism)(AP1 hereinafter refers to control board of the outdoor unit)

Main detection point:

● Whether the unit voltage is too high?

● Whether the work voltage is too low?

Out of step occurs once the unit is powerd on

Out of step (synchronism) occurred during operation

Is stop time of the compressor longer than 3 minutes

Are the compressor wires COMP(UVW) connected correctly? Is connection sequence right? Is the connection made in clockwise direction?

Connect the wires correctly

Replace the control panel AP1

If the fault is eliminated?

Is the outdoor fan working normally

Is the outdoor unit blocked by forein objects

If the input voltage of unit is normal?

If the refrigerant is too much?

Replace the control panel AP1

Check if the fan terminal OFAN is connected correctly

Remove foreign objects (clean heat exchanger and increase

Start to run until the unit resume normal voltage

Charge the refrigerant with technical manual

Replace the capacitor C1

Replace the outdoor fan

Replace the compressor

End

If the fault is eliminated?

Replace the compressor

Ye s

End

8.4.2.7 Overload and discharge malfunction detect (following AP1 for outdoor unit control board)

Main detection point:

● Wether the electronic expansion valve is connected well or not? ● Is electronic expansion valve damaged?

● Is the refrigerant leaked?

20 minutes after the complete unit is powered off

If the overload protector SAT is well connected?

Under amb. Temp., test the resistance of overload

rotector with ohmeic meter, resistance value is 1000Ω

Is the terminal FA for the electronic ex

ansion valve connected correctly?

Connect the wires correctly?

Resistances between the first 4 pins close to the terminal hole and the fifth

in are almost the same, less than 100Ω.

Replace overload protector SAT

Refrigerant leakage, refilling the refrigerant, refer to specification

Replace the electronic expansion valve

Yes

If the fault is eliminated?

Replace the control panel AP1

End

8.4.2.8 Power factor correction (PFC) fault (a fault of outdoor unit) (AP1 hereinafter refers to the control board of the

outdoor unit)

Main detection point:

● Check if the reactor (L) of the outdoor unit and the PFC capacitor are broken?

The failure diagnosis is as follows:

Start

Check wiring of the reactor (L) of the outdoor unit and the PFC capacitor

Whether there is any damage or short-circuit?

Ye s

Replace it as per the wiring diagram and reconnect the wires.

If the fault is eliminated?

Ye s

Remove the PFC capacitor and measure resistance between the two terminals.

Is the resistance around zero?

Disconnect the terminals for the reactor and measure the resistance between the two terminals of the reactor.

Whether there is any damage or short-circuit?

Replace the control panel AP1

End

Ye s

The capacitor is short circuited and the capacitor should be replaced.

Ye s

Replace the reactor

Restart the unit

If the fault is eliminated?

Ye s

8.4.2.9 Communication malfunction (following AP1 for outdoor unit control board)

Main detection point:

● Detect the indoor and outdoor units connection wire and indoor and outdoor units inside wiring is connect well or not, if is

there any damage?

● Is there any damage for the indoor unit mainboard communication circuit? Is communication circuit damaged?

The flow chart for the malfunction detect:

The AP1 voltage detection circuit is at fault

If the fault is eliminated?

Start

Did the unit operate normally before the failure occurs.

Ye s

Are wires broken?

Check the communication circuit of the outdoor unit

The communication circuit is abnormal.

Ye s

Replace the main board (AP1) of the outdoor unit

Check the wiring of the indoor and outdoor units with reference to the wiring diagrams

Is the connection right?

Correctly connect the corresponding wires for the indoor and outdoor units with reference to the wiring diagram.

If the fault is eliminated?

Ye s

Replace the main board of the indoor unit.

If the fault is eliminated?

Ye s

End

Appendix 1: Resistance table for indoor/outdoor ambient temperature sensors (numerical value of resistance) (15K)

Tem p . (° C ) Resistance (kΩ) Temp . (° C ) Resistance (kΩ) Tem p. ( °C) Resistance (kΩ) Temp . (° C ) Resistance (kΩ)

-19 138.100 20 18.750 59 3.848 98 1.071

-18 128.600 21 17.930 60 3.711 99 1.039

-17 121.600 22 17.140 61 3.579 100 1.009

-16 115.000 23 16.390 62 3.454 101 0.980

-15 108.700 24 15.680 63 3.333 102 0.952

-14 102.900 25 15.000 64 3.217 103 0.925

-13 97.400 26 14.360 65 3.105 104 0.898

-12 92.220 27 13.740 66 2.998 105 0.873

-11 87.350 28 13.160 67 2.896 106 0.848

-10 82.750 29 12.600 68 2.797 107 0.825

-9 78.430 30 12.070 69 2.702 108 0.802

-8 74.350 31 11.570 70 2.611 109 0.779

-7 70.500 32 11.090 71 2.523 110 0.758

-6 66.880 33 10.630 72 2.439 111 0.737

-5 63.460 34 10.200 73 2.358 112 0.717

-4 60.230 35 9.779 74 2.280 113 0.697

-3 57.180 36 9.382 75 2.206 114 0.678

-2 54.310 37 9.003 76 2.133 115 0.660

-1 51.590 38 8.642 77 2.064 116 0.642

0 49.020 39 8.297 78 1.997 117 0.625

1 46.600 40 7.967 79 1.933 118 0.608

2 44.310 41 7.653 80 1.871 119 0.592

3 42.140 42 7.352 81 1.811 120 0.577

4 40.090 43 7.065 82 1.754 121 0.561

5 38.150 44 6.791 83 1.699 122 0.547

6 36.320 45 6.529 84 1.645 123 0.532

7 34.580 46 6.278 85 1.594 124 0.519

8 32.940 47 6.038 86 1.544 125 0.505

9 31.380 48 5.809 87 1.497 126 0.492

10 29.900 49 5.589 88 1.451 127 0.480

11 28.510 50 5.379 89 1.408 128 0.467

12 27.180 51 5.197 90 1.363 129 0.456

13 25.920 52 4.986 91 1.363 130 0.444

14 24.730 53 4.802 92 1.282 131 0.433

15 23.600 54 4.625 93 1.244 132 0.422

16 22.530 55 4.456 94 1.207 133 0.412

17 21.510 56 4.294 95 1.171 134 0.401

18 20.540 57 4.139 96 1.136 135 0.391

19 19.630 58 3.990 97 1.103 136 0.382

Appendix 2: Resistance table for indoor/outdoor tube temperature sensor (20K)

Tem p . (° C ) Resistance (kΩ) Temp . (°C ) Resistance (kΩ) Temp . (°C ) Resistance (kΩ) Tem p . (° C ) Resistance (kΩ)

-19 181.400 20 25.010 59 5.130 98 1.427

-18 171.400 21 23.900 60 4.948 99 1.386

-17 162.100 22 22.850 61 4.773 100 1.346

-16 153.300 23 21.850 62 4.605 101 1.307

-15 145.000 24 20.900 63 4.443 102 1.269

-14 137.200 25 20.000 64 4.289 103 1.233

-13 129.900 26 19.140 65 4.140 104 1.198

-12 123.000 27 18.130 66 3.993 105 1.164

-11 116.500 28 17.550 67 3.861 106 1.131

-10 110.300 29 16.800 68 3.729 107 1.099

-9 104.600 30 16.100 69 3.603 108 1.069

-8 99.130 31 15.430 70 3.481 109 1.039

-7 94.000 32 14.790 71 3.364 110 1.010

-6 89.170 33 14.180 72 3.252 111 0.983

-5 84.610 34 13.590 73 3.144 112 0.956

-4 80.310 35 13.040 74 3.040 113 0.930

-3 76.240 36 12.510 75 2.940 114 0.904

-2 72.410 37 12.000 76 2.844 115 0.880

-1 68.790 38 11.520 77 2.752 116 0.856

0 65.370 39 11.060 78 2.663 117 0.833

1 62.130 40 10.620 79 2.577 118 0.811

2 59.080 41 10.200 80 2.495 119 0.770

3 56.190 42 9.803 81 2.415 120 0.769

4 53.460 43 9.420 82 2.339 121 0.746

5 50.870 44 9.054 83 2.265 122 0.729

6 48.420 45 8.705 84 2.194 123 0.710

7 46.110 46 8.370 85 2.125 124 0.962

8 43.920 47 8.051 86 2.059 125 0.674

9 41.840 48 7.745 87 1.996 126 0.658

10 39.870 49 7.453 88 1.934 127 0.640

11 38.010 50 7.173 89 1.875 128 0.623

12 36.240 51 6.905 90 1.818 129 0.607

13 34.570 52 6.648 91 1.736 130 0.592

14 32.980 53 6.403 92 1.710 131 0.577

15 31.470 54 6.167 93 1.658 132 0.563

16 30.040 55 5.942 94 1.609 133 0.549

17 28.680 56 5.726 95 1.561 134 0.535

18 27.390 57 5.519 96 1.515 135 0.521

19 26.170 58 5.320 97 1.470 136 0.509

Note: The informations above are only for reference.

Appendix 3: form for indoor/outdoor unit’s air exhaust temperature sensor numerical value of resistance

Tem p . (° C ) Resistance (kΩ) Tem p. (° C) Resistance (kΩ)Tem p . (° C ) Resistance (kΩ) Temp. (°C ) Resistance (kΩ)

-29 853.500 10 98.000 49 18.340 88 4.754

-28 799.800 11 93.420 50 17.650 89 4.609

-27 750.000 12 89.070 51 16.990 90 4.469

-26 703.800 13 84.950 52 16.360 91 4.334

-25 660.800 14 81.050 53 15.750 92 4.204

-24 620.800 15 77.350 54 15.170 93 4.079

-23 580.600 16 73.830 55 14.620 94 3.958

-22 548.900 17 70.500 56 14.090 95 3.841

-21 519.600 18 67.340 57 13.580 96 3.728

-20 486.500 19 64.330 58 13.090 97 3.619

-19 458.300 20 61.480 59 12.620 98 3.514

-18 432.000 21 58.770 60 12.170 99 3.413

-17 407.400 22 56.190 61 11.740 100 3.315

-16 384.500 23 53.740 62 11.320 101 3.220

-15 362.900 24 51.410 63 10.930 102 3.129

-14 342.800 25 49.190 64 10.540 103 3.040

-13 323.900 26 47.080 65 10.180 104 2.955

-12 306.200 27 45.070 66 9.827 105 2.872

-11 289.600 28 43.160 67 9.489 106 2.792

-10 274.000 29 41.340 68 9.165 107 2.640

-9 259.300 30 39.610 69 8.854 108 2.568

-8 245.600 31 37.960 70 8.555 109 2.498

-7 232.600 32 36.380 71 8.268 110 2.431

-6 220.500 33 34.880 72 7.991 111 2.365

-5 209.000 34 33.450 73 7.726 112 2.302

-4 198.300 35 32.090 74 7.470 113 2.241

-3 199.100 36 30.790 75 7.224 114 2.182

-2 178.500 37 29.540 76 6.998 115 2.124

-1 169.500 38 28.360 77 6.761 116 2.065

0 161.000 39 27.230 78 6.542 117 2.069

1 153.000 40 26.150 79 6.331 118 2.015

2 145.400 41 25.110 80 6.129 119 1.963

3 138.300 42 24.130 81 5.933 120 1.912

4 131.500 43 23.190 82 5.746 121 1.863

5 125.100 44 22.290 83 5.565 122 1.816

6 119.100 45 21.430 84 5.390 123 1.770

7 113.400 46 20.600 85 5.222 124 1.725

8 108.000 47 19.810 86 5.060 125 1.682

9 102.800 48 19.060 87 4.904 126 1.640

Via Gettuglio Mansoldo

(Loc. La Macia) 37040 Arcole

Verona, Italy

Tel. +39 - 045.76.36.585 r.a.

Fax +39 - 045.76.36.551 r.a.

www.maxa.it

e-mail: maxa@maxa.it

MAXA BDS28A, BDS35A Technical Manual

Specifications and Main Features

Frequently Asked Questions

User Manual