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28

<Heating>

Indoor unit combinations

Capacity of each unit (BTU/h)

Total rated

capacity

(BTU/h)

Outdoor

 unit input

(W)

Outdoor unit 

current (A)

Unit

A

B

C

D

E

F

G

Unit A

Unit B

Unit C

Unit D

Unit E

Unit F

Unit G

208V 230V

06

06

12

12

12

12

-

6000

6000

12000

12000

12000

12000

-

60000

4390

21.4 19.4 

06

06

12

12

12

15

-

5710

5710

11430

11430

11430

14290

-

60000

4190

20.5 18.5 

06

06

12

12

12

18

-

5450

5450

10910

10910

10910

16360

-

59990

4010

19.6 17.7 

06

06

12

12

15

15

-

5450

5450

10910

10910

13640

13640

-

60000

4010

19.6 17.7 

06

06

12

12

15

18

-

5220

5220

10430

10430

13040

15650

-

59990

3840

18.8 17.0 

06

06

12

15

15

15

-

5220

5220

10430

13040

13040

13040

-

59990

3840

18.8 17.0 

06

09

09

09

09

09

-

7000

10600

10600

10600

10600

10600

-

60000

5120

25.0 22.6 

06

09

09

09

09

12

-

6630

10030

10030

10030

10030

13250

-

60000

4850

23.7 21.4 

06

09

09

09

09

15

-

6280

9510

9510

9510

9510

15700

-

60020

4610

22.5 20.4 

06

09

09

09

09

18

-

5970

9030

9030

9030

9030

17900

-

59990

4390

21.4 19.4 

06

09

09

09

09

24

-

5430

8220

8220

8220

8220

21710

-

60020

4010

19.6 17.7 

06

09

09

09

12

12

-

6290

9520

9520

9520

12580

12580

-

60010

4610

22.5 20.4 

06

09

09

09

12

15

-

5980

9050

9050

9050

11950

14940

-

60020

4390

21.4 19.4 

06

09

09

09

12

18

-

5690

8620

8620

8620

11380

17080

-

60010

4190

20.5 18.5 

06

09

09

09

12

24

-

5200

7870

7870

7870

10400

20790

-

60000

3840

18.8 17.0 

06

09

09

09

15

15

-

5690

8620

8620

8620

14230

14230

-

60010

4190

20.5 18.5 

06

09

09

09

15

18

-

5430

8230

8230

8230

13580

16300

-

60000

4010

19.6 17.7 

06

09

09

09

18

18

-

5200

7870

7870

7870

15600

15600

-

60010

3840

18.8 17.0 

06

09

09

12

12

12

-

5980

9060

9060

11970

11970

11970

-

60010

4390

21.4 19.4 

06

09

09

12

12

15

-

5700

8630

8630

11400

11400

14250

-

60010

4190

20.5 18.5 

06

09

09

12

12

18

-

5440

8240

8240

10880

10880

16320

-

60000

4010

19.6 17.7 

06

09

09

12

15

15

-

5440

8240

8240

10880

13600

13600

-

60000

4010

19.6 17.7 

06

09

09

12

15

18

-

5200

7880

7880

10410

13010

15610

-

59990

3840

18.8 17.0 

06

09

09

15

15

15

-

5200

7880

7880

13010

13010

13010

-

59990

3840

18.8 17.0 

06

09

12

12

12

12

-

5710

8640

11410

11410

11410

11410

-

59990

4190

20.5 18.5 

06

09

12

12

12

15

-

5450

8250

10900

10900

10900

13620

-

60020

4010

19.6 17.7 

06

09

12

12

12

18

-

5210

7890

10420

10420

10420

15630

-

59990

3840

18.8 17.0 

06

09

12

12

15

15

-

5210

7890

10420

10420

13030

13030

-

60000

3840

18.8 17.0 

06

12

12

12

12

12

-

5450

10910

10910

10910

10910

10910

-

60000

4010

19.6 17.7 

06

12

12

12

12

15

-

5220

10430

10430

10430

10430

13040

-

59980

3840

18.8 17.0 

09

09

09

09

09

09

-

10000

10000

10000

10000

10000

10000

-

60000

4850

23.7 21.4 

09

09

09

09

09

12

-

9490

9490

9490

9490

9490

12540

-

59990

4610

22.5 20.4 

09

09

09

09

09

15

-

9020

9020

9020

9020

9020

14900

-

60000

4390

21.4 19.4 

09

09

09

09

09

18

-

8590

8590

8590

8590

8590

17030

-

59980

4190

20.5 18.5 

09

09

09

09

09

24

-

7850

7850

7850

7850

7850

20740

-

59990

3840

18.8 17.0 

09

09

09

09

12

12

-

9030

9030

9030

9030

11930

11930

-

59980

4390

21.4 19.4 

09

09

09

09

12

15

-

8610

8610

8610

8610

11370

14210

-

60020

4190

20.5 18.5 

09

09

09

09

12

18

-

8220

8220

8220

8220

10850

16280

-

60010

4010

19.6 17.7 

09

09

09

09

15

15

-

8220

8220

8220

8220

13570

13570

-

60020

4010

19.6 17.7 

09

09

09

09

15

18

-

7860

7860

7860

7860

12980

15580

-

60000

3840

18.8 17.0 

09

09

09

12

12

12

-

8620

8620

8620

11380

11380

11380

-

60000

4190

20.5 18.5 

09

09

09

12

12

15

-

8230

8230

8230

10870

10870

13580

-

60010

4010

19.6 17.7 

09

09

09

12

12

18

-

7870

7870

7870

10400

10400

15600

-

60010

3840

18.8 17.0 

09

09

09

12

15

15

-

7870

7870

7870

10400

13000

13000

-

60010

3840

18.8 17.0 

09

09

12

12

12

12

-

8240

8240

10880

10880

10880

10880

-

60000

4010

19.6 17.7 

09

09

12

12

12

15

-

7880

7880

10410

10410

10410

13010

-

60000

3840

18.8 17.0 

09

12

12

12

12

12

-

7890

10420

10420

10420

10420

10420

-

59990

3840

18.8 17.0 

06

06

06

06

06

06

06

7200

7200

7200

7200

7200

7200

7200

50400

4870

23.8 21.5 

06

06

06

06

06

06

09

7200

7200

7200

7200

7200

7200

10900

54100

5060

24.7 22.4 

06

06

06

06

06

06

12

7200

7200

7200

7200

7200

7200

14400

57600

5210

25.5 23.0 

06

06

06

06

06

06

15

7060

7060

7060

7060

7060

7060

17650

60010

5120

25.0 22.6 

06

06

06

06

06

06

18

6670

6670

6670

6670

6670

6670

20000

60020

4850

23.7 21.4 

06

06

06

06

06

06

24

6000

6000

6000

6000

6000

6000

24000

60000

4390

21.4 19.4 

06

06

06

06

06

09

09

7200

7200

7200

7200

7200

10900

10900

57800

5230

25.6 23.1 

06

06

06

06

06

09

12

7050

7050

7050

7050

7050

10670

14090

60010

5120

25.0 22.6 

06

06

06

06

06

09

15

6660

6660

6660

6660

6660

10080

16640

60020

4850

23.7 21.4 

06

06

06

06

06

09

18

6310

6310

6310

6310

6310

9550

18920

60020

4610

22.5 20.4 

Summary of Contents for MXZ-8B48NA

Page 1: ...SED EDITION C Service Ref MXZ 8B48NA MXZ 8B48NAR1 PAC AKA51BC PAC AKA31BC Model name indication HFC utilized R410A November 2010 NOTE This service manual describes technical data of outdoor unit and branch box As for indoor units refer to its service manual RoHS compliant products have G mark on the spec name plate Model name Outdoor unit MXZ 8B48NA Branch box PAC AKA51BC PAC AKA31BC Indispensable...

Page 2: ...tment gauge Gauge manifold Torque wrench Gas leak detector Charge hose Tools for R410A Contamination inside refrigerant piping can cause deterio ration of refrigerant oil etc If dirt dust or moisture enters into refrigerant cycle that can cause deterioration of refrigerant oil or malfunction of com pressor If large amount of mineral oil enters that can cause deterio ration of refrigerant oil etc M...

Page 3: ...e base 7 Refrigerant cylinder Only for R410A Top of cylinder Pink Cylinder with syphon 8 Refrigerant recovery equipment 2 Additional refrigerant charge When charging directly from cylinder Check that cylinder for R410A on the market is syphon type Charging should be performed with the cylinder of syphon stood vertically Refrigerant is charged from liquid phase 1 Cautions for service 1 Perform serv...

Page 4: ...9 52 12 70 15 88 19 05 17 0 43 64 22 0 7 8 26 0 1 3 64 29 0 1 9 64 17 0 22 0 24 0 27 0 36 0 Nominal dimensions inch Flare nut dimensions Outside diameter inch Dimension B mm inch R410A R22 Gauge manifold Charge hose Gas leak detector Refrigerant recovery equipment Refrigerant cylinder Applied oil Safety charger Charge valve Vacuum pump Flare tool Bender Pipe cutter Welder and nitrogen gas cylinder...

Page 5: ... can choose the favorite one 2 branch pipe joint Optional parts In case of using 1 branch box In case of using 2 branch boxes No need Model name Connection method flare brazing MSDD 50AR E MSDD 50BR E Option Optional accessories of indoor units and outdoor units are available MAX capacity kBTU h Cooling Heating 54 60 Ceiling concealed 4 way ceiling cassette Wall mounted Model type Model name Delux...

Page 6: ...to achieve the optimum control 3 2 1 System example 3 2 2 Method for identifying Ŷ Outdoor unit Development No A B etc Power supply N Single phase 208 230V 60Hz Multi type heat pump inverter outdoor unit Indicates equivalent to rated cooling capacity kBTU h Number of connectable indoor units MAX Control and refrigerant A New A control and R410A Service No 1 2 etc M X Z 4 8 8 B N A P A C A K A 5 1 ...

Page 7: ... 15 24 24 18 18 Ŷ System example of 5 indoor units Ŷ Verification The rated capacity should be determined by observing the table below The unit s quantities are limited in 2 to 8 units For the next step make sure that the selected total rated capacity is in a range of 12 70 2 kBTU h The total indoor unit capacity should be within the outdoor units 54 0 kBTU h is preferred Combination of excessive ...

Page 8: ...iping connection size of indoor unit use optional different diameter deformed joints to the branch box side Connect deformed joint directly to the branch box side A B Flare connection employed No brazing A B B B B B Branch box Ŷ In case of using 1 branch box Flare connection employed No brazing A A A B B B B B 2 branches pipe joint optional parts Branch box 1 Branch box 2 Ŷ In case of using 2 bran...

Page 9: ... Fan motor output kW 0 086 0 086 AirÀow m min CFM 100 3 530 Dimensions H W D W mm in 980 37 13 32 D mm in 330 30 13 1 3 16 H mm in 1 350 53 5 32 Weight kg lbs 126 278 Refrigerant R410A Charge kg lbs 8 5 18 7 Oil Model L oz 2 3 73 FV50S Protection devices High pressure protection HP switch Compressor protection Discharge thermo Over current detection MXZ 8B48NA Compressor thermo Over current detect...

Page 10: ...D E 9 52 3 8 4 A B C D 12 7 1 2 1 E PAC AKA51BC PAC AKA31BC Single phase 208 230V 60Hz 0 003 0 05 Galvanized sheets O D 20 O D 3 4 450 17 3 4 280 11 198 7 3 4 9 52 3 8 15 88 5 8 Each 3 wire plus earth wire 3 wire plus earth wire Branch box PAC AKA51BC PAC AKA31BC W The piping connection size differs according to the type and capacity of indoor units Match the piping connection size for indoor and ...

Page 11: ...040 9 9 9 0 09 15 9000 15000 24000 2290 11 2 10 1 09 18 9000 18000 27000 2540 12 4 11 2 09 24 9000 24000 33000 3010 14 7 13 3 12 12 12000 12000 24000 2290 11 2 10 1 12 15 12000 15000 27000 2540 12 4 11 2 12 18 12000 18000 30000 2780 13 6 12 3 12 24 12000 24000 36000 3390 16 5 14 9 15 15 15000 15000 30000 2780 13 6 12 3 15 18 15000 18000 33000 3010 14 7 13 3 15 24 15000 24000 39000 3910 19 1 17 2 1...

Page 12: ...15 15 15000 15000 15000 45000 5190 25 3 22 9 15 15 18 15000 15000 18000 48000 5900 28 8 26 0 15 15 24 15000 15000 24000 54000 5400 26 3 23 8 15 18 18 15000 18000 18000 51000 5620 27 4 24 8 15 18 24 14210 17050 22740 54000 4940 24 1 21 8 15 24 24 12860 20570 20570 54000 4220 20 6 18 6 18 18 18 18000 18000 18000 54000 5400 26 3 23 8 18 18 24 16200 16200 21600 54000 4550 22 2 20 1 18 24 24 14730 1964...

Page 13: ...15 15 15 6000 15000 15000 15000 51000 5620 27 4 24 8 06 15 15 18 6000 15000 15000 18000 54000 5400 26 3 23 8 06 15 15 24 5400 13500 13500 21600 54000 4550 22 2 20 1 06 15 18 18 5680 14210 17050 17050 53990 4940 24 1 21 8 06 15 18 24 5140 12860 15430 20570 54000 4220 20 6 18 6 06 15 24 24 4700 11740 18780 18780 54000 3680 17 9 16 2 06 18 18 18 5400 16200 16200 16200 54000 4550 22 2 20 1 06 18 18 24...

Page 14: ...730 14730 54000 3930 19 2 17 3 15 18 18 18 11740 14090 14090 14090 54010 3680 17 9 16 2 06 06 06 06 06 6000 6000 6000 6000 6000 30000 2780 13 6 12 3 06 06 06 06 09 6000 6000 6000 6000 9000 33000 3010 14 7 13 3 06 06 06 06 12 6000 6000 6000 6000 12000 36000 3390 16 5 14 9 06 06 06 06 15 6000 6000 6000 6000 15000 39000 3910 19 1 17 2 06 06 06 06 18 6000 6000 6000 6000 18000 42000 4510 22 0 19 9 06 0...

Page 15: ... 9000 9000 18000 51000 5620 27 4 24 8 06 09 09 09 24 5680 8530 8530 8530 22740 54010 4940 24 1 21 8 06 09 09 12 12 6000 9000 9000 12000 12000 48000 5900 28 8 26 0 06 09 09 12 15 6000 9000 9000 12000 15000 51000 5620 27 4 24 8 06 09 09 12 18 6000 9000 9000 12000 18000 54000 5400 26 3 23 8 06 09 09 12 24 5400 8100 8100 10800 21600 54000 4550 22 2 20 1 06 09 09 15 15 6000 9000 9000 15000 15000 54000 ...

Page 16: ...09 12 15 24 7040 7040 9390 11740 18780 53990 3680 17 9 16 2 09 09 12 18 18 7360 7360 9820 14730 14730 54000 3930 19 2 17 3 09 09 15 15 15 7710 7710 12860 12860 12860 54000 4220 20 6 18 6 09 09 15 15 18 7360 7360 12270 12270 14730 53990 3930 19 2 17 3 09 09 15 18 18 7040 7040 11740 14090 14090 54000 3680 17 9 16 2 09 12 12 12 12 8530 11370 11370 11370 11370 54010 4940 24 1 21 8 09 12 12 12 15 8100 ...

Page 17: ...940 24 1 21 8 06 06 06 12 12 18 5400 5400 5400 10800 10800 16200 54000 4550 22 2 20 1 06 06 06 12 12 24 4910 4910 4910 9820 9820 19640 54010 3930 19 2 17 3 06 06 06 12 15 15 5400 5400 5400 10800 13500 13500 54000 4550 22 2 20 1 06 06 06 12 15 18 5140 5140 5140 10290 12860 15430 54000 4220 20 6 18 6 06 06 06 12 15 24 4700 4700 4700 9390 11740 18780 54010 3680 17 9 16 2 06 06 06 12 18 18 4910 4910 4...

Page 18: ...09 12 12 12 18 4700 7040 9390 9390 9390 14090 54000 3680 17 9 16 2 06 09 12 12 15 15 4700 7040 9390 9390 11740 11740 54000 3680 17 9 16 2 06 12 12 12 12 12 4910 9820 9820 9820 9820 9820 54010 3930 19 2 17 3 06 12 12 12 12 15 4700 9390 9390 9390 9390 11740 54000 3680 17 9 16 2 09 09 09 09 09 09 9000 9000 9000 9000 9000 9000 54000 5400 26 3 23 8 09 09 09 09 09 12 8530 8530 8530 8530 8530 11370 54020...

Page 19: ... 17 9 16 2 06 06 06 06 15 15 15 4700 4700 4700 4700 11740 11740 11740 54020 3680 17 9 16 2 06 06 06 09 09 09 09 6000 6000 6000 9000 9000 9000 9000 54000 5400 26 3 23 8 06 06 06 09 09 09 12 5680 5680 5680 8530 8530 8530 11370 54000 4940 24 1 21 8 06 06 06 09 09 09 15 5400 5400 5400 8100 8100 8100 13500 54000 4550 22 2 20 1 06 06 06 09 09 09 18 5140 5140 5140 7710 7710 7710 15430 53980 4220 20 6 18 ...

Page 20: ... 06 06 06 06 06 06 15 15 4910 4910 4910 4910 4910 4910 12270 12270 54000 3930 19 2 17 3 06 06 06 06 06 06 15 18 4700 4700 4700 4700 4700 4700 11740 14090 54030 3680 17 9 16 2 06 06 06 06 06 09 09 09 5680 5680 5680 5680 5680 8530 8530 8530 53990 4940 24 1 21 8 06 06 06 06 06 09 09 12 5400 5400 5400 5400 5400 8100 8100 10800 54000 4550 22 2 20 1 06 06 06 06 06 09 09 15 5140 5140 5140 5140 5140 7710 ...

Page 21: ...16 7 15 18 18000 21600 39600 4180 20 4 18 5 15 24 18000 28800 46800 4680 22 9 20 7 18 18 21600 21600 43200 4480 21 9 19 8 18 24 21600 28800 50400 4870 23 8 21 5 24 24 28800 28800 57600 5210 25 5 23 0 06 06 06 7200 7200 7200 21600 2180 10 7 9 6 06 06 09 7200 7200 10900 25300 2580 12 6 11 4 06 06 12 7200 7200 14400 28800 2960 14 5 13 1 06 06 15 7200 7200 18000 32400 3360 16 4 14 8 06 06 18 7200 7200...

Page 22: ... 4 15 15 15 18000 18000 18000 54000 5050 24 7 22 3 15 15 18 18000 18000 21600 57600 5210 25 5 23 0 15 15 24 16670 16670 26670 60010 4850 23 7 21 4 15 18 18 17650 21180 21180 60010 5120 25 0 22 6 15 18 24 15790 18950 25260 60000 4610 22 5 20 4 15 24 24 14290 22860 22860 60010 4190 20 5 18 5 18 18 18 20000 20000 20000 60000 4850 23 7 21 4 18 18 24 18000 18000 24000 60000 4390 21 4 19 4 18 24 24 1636...

Page 23: ...5 7060 17650 17650 17650 60010 5120 25 0 22 6 06 15 15 18 6670 16670 16670 20000 60010 4850 23 7 21 4 06 15 15 24 6000 15000 15000 24000 60000 4390 21 4 19 4 06 15 18 18 6320 15790 18950 18950 60010 4610 22 5 20 4 06 15 18 24 5710 14290 17140 22860 60000 4190 20 5 18 5 06 15 24 24 5220 13040 20870 20870 60000 3840 18 8 17 0 06 18 18 18 6000 18000 18000 18000 60000 4390 21 4 19 4 06 18 18 24 5450 1...

Page 24: ...6360 16360 60000 4010 19 6 17 7 15 18 18 18 13040 15650 15650 15650 59990 3840 18 8 17 0 06 06 06 06 06 7200 7200 7200 7200 7200 36000 3770 18 4 16 7 06 06 06 06 09 7200 7200 7200 7200 10900 39700 4190 20 5 18 5 06 06 06 06 12 7200 7200 7200 7200 14400 43200 4480 21 9 19 8 06 06 06 06 15 7200 7200 7200 7200 18000 46800 4680 22 9 20 7 06 06 06 06 18 7200 7200 7200 7200 21600 50400 4870 23 8 21 5 06...

Page 25: ...21070 59980 5120 25 0 22 6 06 09 09 09 24 6290 9520 9520 9520 25150 60000 4610 22 5 20 4 06 09 09 12 12 7200 10900 10900 14400 14400 57800 5230 25 6 23 1 06 09 09 12 15 7040 10650 10650 14070 17590 60000 5120 25 0 22 6 06 09 09 12 18 6650 10060 10060 13290 19940 60000 4850 23 7 21 4 06 09 09 12 24 5980 9060 9060 11970 23930 60000 4390 21 4 19 4 06 09 09 15 15 6650 10060 10060 16620 16620 60010 485...

Page 26: ... 18 5 09 09 12 15 24 7880 7880 10410 13010 20820 60000 3840 18 8 17 0 09 09 12 18 18 8240 8240 10880 16320 16320 60000 4010 19 6 17 7 09 09 15 15 15 8630 8630 14250 14250 14250 60010 4190 20 5 18 5 09 09 15 15 18 8240 8240 13600 13600 16320 60000 4010 19 6 17 7 09 09 15 18 18 7880 7880 13010 15610 15610 59990 3840 18 8 17 0 09 12 12 12 12 9550 12610 12610 12610 12610 59990 4610 22 5 20 4 09 12 12 ...

Page 27: ...0 4610 22 5 20 4 06 06 06 12 12 18 6000 6000 6000 12000 12000 18000 60000 4390 21 4 19 4 06 06 06 12 12 24 5450 5450 5450 10910 10910 21820 59990 4010 19 6 17 7 06 06 06 12 15 15 6000 6000 6000 12000 15000 15000 60000 4390 21 4 19 4 06 06 06 12 15 18 5710 5710 5710 11430 14290 17140 59990 4190 20 5 18 5 06 06 06 12 15 24 5220 5220 5220 10430 13040 20870 60000 3840 18 8 17 0 06 06 06 12 18 18 5450 ...

Page 28: ...9 12 12 12 18 5210 7890 10420 10420 10420 15630 59990 3840 18 8 17 0 06 09 12 12 15 15 5210 7890 10420 10420 13030 13030 60000 3840 18 8 17 0 06 12 12 12 12 12 5450 10910 10910 10910 10910 10910 60000 4010 19 6 17 7 06 12 12 12 12 15 5220 10430 10430 10430 10430 13040 59980 3840 18 8 17 0 09 09 09 09 09 09 10000 10000 10000 10000 10000 10000 60000 4850 23 7 21 4 09 09 09 09 09 12 9490 9490 9490 94...

Page 29: ... 0 06 06 06 06 15 15 15 5220 5220 5220 5220 13040 13040 13040 60000 3840 18 8 17 0 06 06 06 09 09 09 09 6630 6630 6630 10030 10030 10030 10030 60010 4850 23 7 21 4 06 06 06 09 09 09 12 6290 6290 6290 9520 9520 9520 12580 60010 4610 22 5 20 4 06 06 06 09 09 09 15 5980 5980 5980 9050 9050 9050 14940 60030 4390 21 4 19 4 06 06 06 09 09 09 18 5690 5690 5690 8620 8620 8620 17080 60010 4190 20 5 18 5 06...

Page 30: ...6 17 7 06 06 06 06 06 06 15 15 5450 5450 5450 5450 5450 5450 13640 13640 59980 4010 19 6 17 7 06 06 06 06 06 06 15 18 5220 5220 5220 5220 5220 5220 13040 15650 60010 3840 18 8 17 0 06 06 06 06 06 09 09 09 6290 6290 6290 6290 6290 9520 9520 9520 60010 4610 22 5 20 4 06 06 06 06 06 09 09 12 5980 5980 5980 5980 5980 9060 9060 11970 59990 4390 21 4 19 4 06 06 06 06 06 09 09 15 5700 5700 5700 5700 5700...

Page 31: ...under the stated conditions o Total capacity at the rated time Rated cooling capacity Rated heating capacity Indoor D B 80 F W B 67 F Outdoor D B 95 F Indoor D B 70 F Outdoor D B 47 F W B 43 F Fig 1 1 Cooling capacity Fig 1 2 Cooling input 5 0 5 10 15 20 25 30 35 40 46 C W B 16 60 8 18 64 4 20 68 22 71 6 0 6 0 8 1 1 2 1 4 Cooling capacity ratio Outdoor intake air dry bulb temperature 25 32 41 50 5...

Page 32: ...ity correction factor 2 Method for Obtaining the Corrected Piping Length Corrected piping length Actual piping length between outdoor unit and the farthest indoor unit 0 30 o number of bends in the piping m ft Fig 3 Cooling capacity correction curve 9 11 1 27 50 40 5 75 54 0 100 70 2 130 0 65 20 40 60 80 m 20 40 60 80 0 70 0 75 0 80 0 85 0 90 0 95 1 00 70 130 195 260 ft Cooling Capacity ratio Tota...

Page 33: ...0 50 40 30 20 10 63 125 250 500 1000 2000 4000 8000 APPROXIMATE THRESHOLD OF HEARING FOR CONTINUOUS NOISE OCTAVE BAND SOUND PRESSURE LEVEL dB 0 dB 0 0002 bar BAND CENTER FREQUENCIES Hz NC 60 NC 50 NC 40 NC 30 NC 20 NC 70 MXZ 8B48NA MXZ 8B48NAR1 COOLING MODE HEATING 54 SPL dB 55 LINE ...

Page 34: ...ner side of each panel mm inch FOUNDATION Service space Min 1000mm 39 3 8 Min 10mm 3 8 Min 10mm 3 8 FREE Min 150mm 5 29 32 2 U Shaped notched hole Foundation Bolt M10 W3 8 Conduit hole 2 W27 1 1 16 Knockout 45 1 25 32 Right trunking hole Knockout 45 1 25 32 40 1 9 16 65 2 9 16 92 3 5 8 27 1 1 16 55 2 3 16 23 29 32 73 2 7 8 63 2 1 2 Rear piping hole Knockout Rear trunking hole Knockout Conduit hole...

Page 35: ...3 8F 1 2F 5 8F GAS PIPE TO OUT DOOR UNIT E D C B A 3 8F 1 4F 1 4F 1 4F 1 4F 1 4F LIQUID PIPE TERMINALBLOCK TO INDOOR UNIT TERMINALBLOCK TO OUTDOOR UNIT 50 2 50 2 TB3B TB3A TB3C TB2B When installing the conduit Set the attachment to the inner side of each panel 3 W22 7 8 56 2 1 4 192 7 1 2 58 2 1 4 50 2 CONDUIT PLATE ELECTRIC COVER 3 WIRE BAND 68 70 79 61 25 25 25 73 TERMINALBLOCK TO OUTDOOR UNIT D...

Page 36: ...36 7 WIRING DIAGRAM 7 1 OUTDOOR UNIT MXZ 8B48NA MXZ 8B48NAR1 The black square Ŷ indicates a switch position L2 Phase Compressor The black square Ŷ indicates a switch posotion L1 Phase ...

Page 37: ...37 7 2 BRANCH BOX PAC AKA51BC PAC AKA31BC Setup of SW1 Make it the same setup as former when exchanging PCB The black square Ŷ indicates a switch position ...

Page 38: ...ve SV1 High pressure sensor discharge pressure sensor 63HS Accumulator 4 way valve Distributor with Strainer Refrigerant flow in cooling Refrigerant flow in heating Thermistor TH4 For MXZ 8B48NAR1 Compressor temperature Outdoor unit MXZ 8B48NA MXZ 8B48NAR1 PAC AKA51BC PAC AKA31BC Branch box Capillary tube 1 For return of oil from oil separator Capillary tube 2 For SV2 Capillary tube 3 ahead of LEV...

Page 39: ...ing to 9 4 TROUBLESHOOTING BY INFERIOR PHENOMENA The trouble is not reoccurring Logged Not logged Consider the temporary defects such as the work of protection devices in the refrigerant circuit including compressor poor connection of wiring noise and etc Re check the symptom and check the installation environment refrigerant amount weather when the trouble occurred matters related to wiring and e...

Page 40: ...n of refrigerant in the compressor The resistance will rise above 1M after the compressor is warmed up for 4 hours The time necessary to warm up the compressor varies according to atmos pheric conditions and refrigerant accumulation To operate the compressor with refrigerant accumulated in the compressor the compressor must be warmed up at least 12 hours to prevent breakdown 4 If the insulation re...

Page 41: ...the test run from outdoor unit all indoor units operate Therefore you cannot detect any erroneous con nection of refrigerant pipes and the connecting wires If it aims at detection of any erroneous connection be sure to carry out the test run from remote controller with reference to 1 Using remote controller SW4 1 SW4 2 SW4 1 SW4 2 ON OFF ON ON Cooling operation Heating operation After performing t...

Page 42: ...fter power sup ply 63L Low pressure switch 1 Disconnection or contact failure of 63L connector on outdoor controller circuit board 2 Disconnection or contact failure of 63L 3 63L is operating due to refriger ant leakage or defective parts 4 Defective outdoor controller circuit board 1 Check connection of 63L connector on outdoor controller circuit board Refer to 9 7 2 Check the 63L side of connect...

Page 43: ...or branch box controller circuit board can automatically check the number of connected indoor units Abnormal if the number cannot be checked automatically due to miswiring of indoor branch box branch box out door unit connecting wire and etc after power is turned on for 4 minutes 1 Check disconnection or looseness or polar ity of indoor branch box branch box outdoor unit connecting wire of indoor ...

Page 44: ...is time check delay code U1 will be displayed 1 Short cycle of indoor unit 2 Clogged filter of indoor unit 3 Decreased airflow caused by dirt of indoor fan 4 Dirt of indoor heat exchanger 5 Locked indoor fan motor 6 Malfunction of indoor fan motor 7 Defective operation of stop valve Not fully opened 8 Clogged or broken pipe 9 Locked outdoor fan motor 10 Malfunction of outdoor fan motor 11 Short cy...

Page 45: ... High pressure sensor defec tive 2 Discharge temperature ther mistor defective 3 Thermistor input circuit defective and high pressure sensor defective in outdoor controller board 5 Error detection of TH7 TH3 1 Thermistor defective 2 Thermistor input circuit defective in outdoor control ler board 1 Check intake superheat Check leakage of refrigerant Charge additional refrigerant 2 Check if stop val...

Page 46: ...e circuit 12 Check outdoor fan 3 Check air flow path for cooling 4 Check if there is something which causes temperature rise around outdoor unit Upper limit of ambient temperature is 46 115 F Turn off power and on again to check if U5 is displayed within 30 minutes If U4 is displayed instead of U5 follow the action to be taken for U4 5 Check resistance value of thermistor TH8 or temperature by mic...

Page 47: ...tarts operating for 10 minutes 2 Erroneous connection of refrigerant pipes or the connecting wires Consider the stopping indoor unit abnormal if condenser evaporator temperature ther mistor TH5 or RT12 detects 5 23 F or below continuously for 5 minutes during a compressor s operation in cooling mode 1 Disconnection or loose connection of discharge com pressor temperature thermistor TH4 2 Defective...

Page 48: ...cuit board 3 Defective communication circuit of indoor branch box controller board 4 Noise has entered into indoor branch box branch box outdoor unit connecting wire 1 Check disconnection or looseness of indoor branch box branch box outdoor unit connecting wire of indoor or branch box or outdoor units 2 4 Turn the power off and on again to check Replace indoor controller board or branch controller...

Page 49: ...ntroller circuit board and the outdoor power circuit board 3 Defective communication circuit of outdoor power circuit board 4 Defective communication circuit of outdoor controller circuit board for outdoor power circuit board 12 Check connection of each connector CN2 and CN4 between the outdoor controller circuit board and the outdoor power circuit board 3 Replace outdoor power circuit board 4 Rep...

Page 50: ...at exchanger 6 Remove the blockage 7 Check refrigerant system during opera tion 3 1For 3 minutes after temperature adjuster turns off the compressor will not start operating even if tem perature adjuster is turned on 2For 3 minutes after temperature adjuster turns on the compressor will not stop operating even if tem perature adjuster is turned off Compressor stops operating immediately when turni...

Page 51: ...on noise of the outdoor unit can be reduced by about 3 4 dB The low noise mode will be activated when a commercially available timer or the contact input of an ON OFF switch is added to the CNDM connector optional parts on the control board of the outdoor unit The capacity may be insufficient according to the outdoor temperature and conditions etc 1 Complete the circuit as shown when using the ext...

Page 52: ...At the ambient temperature 20 68 F Solenoid valve coil Four way valve 21S4 Motor for compressor MC Normal Abnormal Open or short Measure the resistance between the terminals with a tester At the ambient temperature 20 68 F Normal Abnormal Open or short Solenoid valve coil Bypass valve SV2 Measure the resistance between the terminals with a tester At the ambient temperature 20 68 F Normal 1327 10 A...

Page 53: ...ctor CNF1 2 Fuse check Check the fuse F5 on outdoor controller board Power supply check Remove the connector CNF1 2 Measure the voltage in the outdoor controller circuit board TEST POINT VDC between 1 and 4 of the fan connector VDC DC280 350V TEST POINT VCC between 5 and 4 of the fan connector VCC DC15V Wiring recovery Replace outdoor controller board Replace the fan motor Replace outdoor controll...

Page 54: ... 3k 25 77 F 5 2k 30 86 F 4 3k 40 104 F 3 0k Thermistor R0 15k 3 B constant 3480 2 Rt 15exp 3480 273 t 273 1 1 t F 32 1 8 Thermistor R120 7 465k 2 B constant 4057 2 Rt 7 465exp 4057 273 t 393 1 1 20 68 F 250k 30 86 F 160k 40 104 F 104k 50 122 F 70k 60 140 F 48k 70 158 F 34k 80 176 F 24k 90 194 F 17 5k 100 212 F 13 0k 110 230 F 9 8k High temperature thermistor Thermistor Discharge Compressor TH4 t F...

Page 55: ...re the resistance with a tester At the ambient temperature 10 30 50 F 86 F Disconnect the connector then measure the resistance with a tester Winding temperature 20 68 F Thermistor TH A E Gas pipe Normal 4 3k 9 6k Abnormal Open or short Normal Red White Red Orange Brown Yellow Brown Blue Abnormal 46 4 Linear expansion valve LEV A E Open or short ...

Page 56: ...ed sound can be heard No sound is heard when the pulse number moves from B to A in case coil is burnt out or motor is locked by open phase Sound can be detected by placing the ear against the screw driver handle while putting the screw driver to the linear expansion valve LEV M 1 6 4 4 3 2 1 2 1 Red Brown Blue Orange Yellow White 3 4 5 6 Connector LEV A LEV B LEV C LEV D LEV E DC12V branch box con...

Page 57: ... Be sure to attach the stopper to pipe B B A How to attach the coil Hold the lower part of the main body shown as A firmly so that the main body does not move and attach the coil by inserting it downward into the main body Then securely attach the coil stop per to pipe B At this time be careful that stress is not added to lead wire and main body is not wound by lead wire If the stop per is not fir...

Page 58: ...e should be fully closed when the fan is operating The temperature measured by the temperature sensor will drop if there is any leakage If the measured temperature is significantly lower than that on the remote controller this indicates that the valve is not closed It is not necessary to replace the linear expansion valve if the leak of refrigerant is small and does not cause a malfunction Check i...

Page 59: ...ut of low noise mode 1 to 3 Input of external con tact point TH4 Thermistor Discharge Compressor TH3 Thermistor Outdoor pipe TH7 6 Thermistor Outdoor 2 phase pipe CNDC 280 350V DC 1 3 Connect to outdoor power circuit board CNDC VFG TEST POINT 4 Voltage between right pins of PC5C and PC5D pin 3 and pin 4 Same as CNF17 4 VSP TEST POINT 3 Voltage between pins of C5A C5B DC 0V when stopped DC 1 6 5V w...

Page 60: ...e compres sor MC Voltage among phases 10 V 180 V AC CNDC 280 350 V DC 1 3 Connect to the outdoor controller circuit board CNDC E2 E3 Connect to the earth CN52C 52C driving signal Connect to the outdoor controller circuit board CN52C CN2 Connect to the outdoor controller circuit board CN2 1 5 Transmitting signal to outdoor controller circuit board 0 5 V DC 2 5 Zero cross signal 0 5 V DC 3 4 18 V DC...

Page 61: ...ch box Indoor unit connecting wire TB3A to TB3C for PAC AKA31BC LED1 Transmission start up state display Start up LED1 blinks 0 5sec ON 0 5sec OFF Start up completion LED1 lights LED3 5 Not used LED2 Transmission Branch box outdoor Reception state display on branch box side Branch box No 1 LED2 blinks once 0 1sec ON 0 9sec OFF Branch box No 2 LED2 blinks twice 0 1sec ON 0 1sec OFF 0 1sec ON 0 7sec...

Page 62: ...r 2 2 blinking LED2 branch box controller board 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 9 8 FUNCTION OF SWITCHES CONNECTORS AND JUMPERS 1 Function of switches MXZ 8B48NA MXZ 8B48NAR1 The black square Ŷ indicates a switch position Forced defrost should be done as follows 1 Change the DIP SW1 1 on the outdoor controller ...

Page 63: ...nction Effective timing Action by the switch operation No function Switching the target sub cool Heating mode No function No function Demand switching function No function Max Frequency down No function No function No function No function No function No function Switch SW5 SW7 Dip switch SW8 Type of Switch Target sub cool down Capability cut 50 Active Normal Normal Normal Always Always Always 1 2 ...

Page 64: ...0 E7 63L connector red is open 63H connector yellow is open 2 connectors 63H 63L are open Branch box outdoor communication error Signal receiving error Outdoor unit Indoor branch box communication error Signal receiving error Branch box Branch box outdoor communication error Transmitting error Outdoor unit Indoor branch box communication error Transmitting error Branch box Miswiring of indoor bran...

Page 65: ...ayed by turns Example When 2450 hours 245 10 hours 0 5 secs 0 5secs 2 secs 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 Compressor operating current 0 50 LEV opening pulse 0 500 0 50 w Omit the figures after the decimal fractions 0 500 When it is 100 pulse or more hundreds digit tens digit and ones digit are displayed by turns Example When 150 pulse 0 5 secs 0 5secs 2 secs A Pulse Error postponeme...

Page 66: ... Example When 130 0 5 secs 0 5secs 2 secs A Code display Code display 0 50 When no error history 0 and are displayed by turns When no error history 0 and are displayed by turns 1 ON 2 3 4 5 6 Thermo ON time 0 999 Test run elapsed time 0 120 0 999 When it is 100 minutes or more the hundreds digit tens digit and ones digit are displayed by turns Example When 245 minutes 0 5 secs 0 5secs 2 secs 0 120...

Page 67: ...n the temperature is 0 F or less and temperature are displayed by turns ETm 38 190 Pdm 0 711 When the temperature is 0 F or less and temperature are displayed by turns F F PSIG F 46 102 When the temperature is 100 F or more the hun dreds digit tens digit and ones digit are displayed by turns Branch box pipe temperature gas 38 190 Targeted evaporating temperature ETm Cooling 38 190 Targeted high pr...

Page 68: ...dreds digit tens digit and ones digit are displayed by turns V 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 SW2 setting 1 ON 2 3 4 5 6 Display detail Explanation for display Unit F 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 Indoor setting temperature 62 86 Outdoor pipe temperature 2 phase TH6 38 190 Outdoor heatsink temperature TH8 40 327 62 86 F F F 38 190 When the...

Page 69: ... Error thermistor display When there is no error thermistor is displayed Code display Operation frequency on error occurring 0 255 0 255 When it is 100Hz or more hundreds digit tens digit and ones digit are displayed by turns Example When 125Hz 0 5 secs 0 5secs 2 secs 1 ON 2 3 4 5 6 Hz Fan step on error occurring 0 10 0 10 1 ON 2 3 4 5 6 Step 25 1 1 ON 2 3 4 5 6 Pulse LEV opening pulse on error oc...

Page 70: ...00 40 200 When the temperature is 0 C or less and temperature are displayed by turns When the temperature is 100 C or more hundreds digit tens digit and ones digit are displayed by turns 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 15 15 15 15 Indoor unit 1 Indoor unit 2 Indoor unit 3 Indoor unit 4 Indoor unit 5 Indoor unit 6 Indoor unit 7 Indoor unit 8 0 1 0 1 0 1 0 ...

Page 71: ...e difference between room temperature and set temperature Tj 0 99 C Ŷ Tens digit of code current Tj Ŷ Units digit of code Tj a minute ago Tj Cooling Heating Tj room temp í Set temp Tj Set temp í room temp Code of the difference between room temperature and set temperature Tj 0 1 2 3 4 5 6 7 8 9 000 100 010 110 001 101 011 111 Indoor unit 1 Indoor unit 2 Indoor unit 3 Indoor unit 4 Indoor unit 5 In...

Page 72: ...re Liquid TH3 40 90 C 40 194 F w 40 90 C 40 194 F When the coil thermistor detects 0 or below and temperature are displayed by turns Example When 10 0 5 secs 0 5secs 2 secs C F w 10 1 ON 2 3 4 5 6 Discharge Compressor temperature TH4 3 217 C 37 327 F w 3 217 C 37 327 F w When the discharge compressor thermistor detects 100 or more hundreds digit tens digit and ones digit are displayed by turns Exa...

Page 73: ...display Code display Code display 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 Capacity setting indoor D Code display LEV D opening pulse 0 500 0 500 When it is 100 pulse or more hundreds digit tens digit and ones digit are displayed by turns Example When 150 pulse 0 5 secs 0 5secs 2 secs Pulse 1 50 LEV E opening pulse 0 500 0 500 When it is 100 pulse or more hundreds digit tens digit and ones digit are displaye...

Page 74: ...re is 0 or less and temperature are displayed by turns C F w 39 88 C 38 190 F When the temperature is 0 or less and temperature are displayed by turns 0 500 C F w Pulse Pulse 0 500 Indoor pipe temperature Liquid TH2 Indoor E 39 88 C 38 190 F w LEV 1 opening pulse 0 500 1 ON 2 3 4 5 6 Pulse 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 LEV 3 opening pulse 0 500 LEV 4 opening pulse 0 500 0 500 Pulse Pulse 0 500 LEV...

Page 75: ...Cond Eva TH5 Indoor A 39 88 C 38 190 F w C F w Indoor pipe temperature Cond Eva TH5 Indoor B 39 88 C 38 190 F w 1 ON 2 3 4 5 6 C F w Indoor pipe temperature Cond Eva TH5 Indoor C 39 88 C 38 190 F w 1 ON 2 3 4 5 6 C F w Indoor pipe temperature Cond Eva TH5 Indoor D 39 88 C 38 190 F w Indoor pipe temperature Cond Eva TH5 Indoor E 39 88 C 38 190 F w 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 C F w 1 ON 2 3 4 5 6 ...

Page 76: ...9 88 C 38 190 F w C F w Branch pipe temperature TH D 39 88 C 38 190 F w C F w Branch pipe temperature TH E 39 88 C 38 190 F w TH1 Indoor A 8 39 C 46 102 F w TH1 Indoor B 8 39 C 46 102 F w 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 C F w C F w TH1 Indoor C 8 39 C 46 102 F w TH1 Indoor D 8 39 C 46 102 F w 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 C F w C F w C F w 8 39 C 46 102 F w 1 ON 2 3 4 5...

Page 77: ...rature Indoor B 16 31 C 60 87 F w Indoor setting temperature Indoor C 16 31 C 60 87 F w Indoor setting temperature Indoor D 16 31 C 60 87 F w C F w Indoor setting temperature Indoor E 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 1 ON 2 3 4 5 6 C F w C F w C F w C F w 16 31 C 60 87 F w w SW1 8 OFF Unit C SW1 8 ON Unit F ...

Page 78: ...he indoor unit that is connected with remote controller ta A ta B ta A ta A No 3 The data of the sensor on main remote controller ta C ta C ta C ta C OUTDOOR INDOOR REMOTE MAIN REMOTE SUB INDOOR OUTDOOR INDOOR REMOTE MAIN REMOTE SUB OUTDOOR INDOOR REMOTE MAIN OUTDOOR INDOOR REMOTE MAIN REMOTE SUB INDOOR Function Settings Mode No Setting No Initial setting when sent from the factory Remarks Power f...

Page 79: ...artitions Indoor unit All refrigerant of this system will leak out to this room if there is leakage at this indoor unit Direction of refrigerant flow Outdoor unit Maximum concentration Maximum refrigerant concentration of R410A of a room is 0 30 kg K accordance with the installation guidelines To facilitate calculation the maximum concentration is expressed in units of O K kg of R410A per K KHK in...

Page 80: ...perform the same calculations for the larger second and third room etc until it has been determined that nowhere will the maximum concentration be exceeded b There are partitions but there are openings that allow the effective mixing of air c If the smallest room has mechanical ventilation Apparatus that is linked to a household gas detection and alarm device the calculations should be performed f...

Page 81: ...pressure switch solenoid valve coil 4 way valve and solenoid valve coil Hot gas bypass solenoid valve coil Returning oil bypass Then remove a screw 4 8 from the valve bed to remove the lead wire Pull out the disconnected wire from the electrical parts box Diagram symbol in the connector housing Fan motor CNF1 CNF2 Thermistor Outdoor pipe TH3 Thermistor Discharge Compressor TH4 Thermistor Outdoor 2...

Page 82: ...trical parts box 4 Loosen the clamp for the lead wire in the rear of the elec trical parts box See Photo 4 5 Pull out the thermistor Outdoor TH7 from the sensor holder Note In case of replacing thermistor Outdoor TH7 replace it together with thermistor Outdoor 2 phase pipe TH6 since they are combined together Refer to No 4 above to remove thermistor Outdoor 2 phase pipe Photo 6 Clamp Controller ci...

Page 83: ...olenoid valve coil 4 way valve fixing screw 9 Removing solenoid valve coil Bypass valve SV1 and bypass valve 1 Remove the service panel See Figure 1 2 Remove the top panel See Figure 1 3 Remove the electrical parts box See Photo 3 4 Remove 3 right side panel fixing screws 5 12 in the rear of the unit and remove the right side panel 5 Remove the bypass valve coil fixing screw M4 6 6 Remove the sole...

Page 84: ...from heating 100 C 210 F or more then braze the pipes so that the inside of pipes are not oxidized 12 Removing the high pressure sensor 63HS 1 Remove the service panel See Figure 1 2 Remove the top panel See Figure 1 3 Remove the electrical parts box See Photo 3 4 Remove 3 right side panel fixing screws 5 o 12 in the rear of the unit and remove the right side panel 5 Pull out the lead wire of high...

Page 85: ...e piping to remove the pan w When removing the drain pan be careful with remain ing water on the pan Also be careful not to make cracks on the pan Photo 2 Drain pan 3 Removing the thermistors TH A E 1 Remove the controller cover See Photo 1 2 Remove the under panel See Photo 1 3 Pull out the thermistors TH A E from the sensor holders mounted on the gas pipe See Photo 3 4 Pull out those thermistors...

Page 86: ...e side of the branch box See Photo 4 4 Tilt the separator to the board side See Photo 4 5 Loosen the side clamps of the board and disconnect the connectors on the board 6 Pull out the lead wire through the U shaped hole See Photo 3 7 Cut the band that fixes the lead wire to pull out the LEV coil LEV A E See Photo 5 Photo 4 Separator fixing screws Separator Photo 5 Separator LEV coil Band ...

Page 87: ...87 ...

Page 88: ...RING CO LTD Distributed in Nov 2010 No OCH468 REVISED EDITION C Distributed in Sep 2010 No OCH468 REVISED EDITION B PDF 5 Distributed in Jun 2010 No OCH468 REVISED EDITION A PDF 5 Distributed in Feb 2010 No OCH468 PDF 5 Made in Japan New publication effective Nov 2010 Specifications subject to change without notice ...

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