Mitsubishi MXZ-2A20NA User manual

Inverter-controlled multi system type
Models
SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················6
3. INDOOR UNIT OPERATIONAL CHARACTERISTICS····7
4. SPECIFICATION···············································18
5. OUTLINES AND DIMENSIONS ·······················21
6. WIRING DIAGRAM ··········································25
7. REFRIGERANT SYSTEM DIAGRAM··············30
8. DATA·································································36
9. ACTUATOR CONTROL····································52
10. SERVICE FUNCTIONS·····································52
11. TROUBLESHOOTING······································54
12. DISASSEMBLY INSTRUCTIONS·····················71
13. PARTS LIST······················································80
14. RoHS PARTS LIST···········································88
15. OPTIONAL PARTS·········································100
No. OB444
REVISED EDITION-C
The Slim Line.
From Mitsubishi Electric. TM
OUTDOOR UNIT
MXZ-2A20NA
MXZ-2A20NA -
MXZ-3A30NA
MXZ-3A30NA -
MXZ-4A36NA 1
1
MXZ-2A20NA
MXZ-2A20NA - 1
Indoor unit service manual
MSZ-A·NA Series (OB450)
Revision C:
• MXZ-4A36NA have been added.
NOTE:
• This service manual describes technical
data of the outdoor units.
• RoHS compliant products have <G> mark
on the spec name plate.
For servicing of RoHS compliant products,
refer to the RoHS Parts List.
Please void OB444 REVISED EDITION-B.
SPLIT-TYPE, HEAT PUMPAIR CONDITIONERS
HFC
utilized
R410A
33223
9700058
OB444C--1.qxp 07.10.18 2:17 PM Page 1

TECHNICAL CHANGES
2
1
MXZ-2A20NA
New model
MXZ-30TN2 ➔MXZ-3A30NA
1. Combinations of connectable indoor units have been increased.
2. Capacity class of connectable indoor units have been made larger.
3. Compressor has been changed. (THV247FBA ➔TNB220FMCH)
4. Outdoor fan motor has been changed. (RA6N60-AA ➔RC0J60-AB)
5. Refrigerant has been changed. (R22 ➔R410A)
6. Refrigerant system diagram has been changed.
•1 of 2 high pressure switch has been removed.
•Accumulator has been removed.
•Receiver has been added.
7. Communication system has been changed.
8. Power supply way has been changed(change to supply to outdoor unit).
9. Evaporation temperature thermistor has been added.
10. Ambient temperature thermistor has been added.
MXZ-2A20NA ➔MXZ-2A20NA -
1. Compressor has been changed. (SNB130FPDH1 ➔SNB130FQBH1)
2. Gas pipe temperature thermistor has been removed.
3. Pre-heat control has been added.
4. Electronic control P.C. board has been changed.
5. Power board has been changed.
MXZ-3A30NA ➔MXZ-3A30NA -
1. Ball valve has been changed to stop valve.
2. Gas pipe temperature thermistor has been removed.
3. Pre-heat control has been added.
4. Auto line correcting function has been added.
5. Noise filter P.C. board has been changed.
6. Electronic control P.C. board has been changed.
7. Weight has been changed. (158lb. ➔ 148lb.)
MXZ-4A36NA
New model
1
1
Revision A:
•RoHS PARTS LIST has been added.
Revision B:
•MXZ-2A20NA - and MXZ-3A30NA - have been added.
11
Revision C:
•MXZ-4A36NA has been added.
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3
INFORMATION FOR THE AIR CONDITIONER WITH R410A REFRIGERANT
•This room air conditioner adopts HFC refrigerant (R410A) which never destroys the ozone layer.
•Pay particular attention to the following points, though the basic installation procedure is same as that for R22 air
conditioners.
1As R410A has working pressure approximate 1.6 times as high as that of R22, some special tools and piping parts/
materials are required. Refer to the table below.
2Take sufficient care not to allow water and other contaminations to enter the R410A refrigerant during storage and
installation, since it is more susceptible to contaminations than R22.
3For refrigerant piping, use clean, pressure-proof parts/materials specifically designed for R410A. (Refer to 2. Refrigerant
piping.)
4Composition change may occur in R410A since it is a mixed refrigerant. When charging, charge liquid refrigerant to prevent
composition change.
Refrigeration
oil
Refrigerant
New refrigerant
R410A
HFC-32: HFC-125 (50%:50%)
Pseudo-azeotropic refrigerant
Not included
A1/A1
72.6
-60.5
225.82
3.995
Non combustible
0
1730
From liquid phase in cylinder
Possible
Incompatible oil
Non
Non
Previous refrigerant
R22
R22 (100%)
Single refrigerant
Included
A1
86.5
-41.4
136.34
2.772
Non combustible
0.055
1700
Gas phase
Possible
Compatible oil
Light yellow
Non
Refrigerant
Composition (Ratio)
Refrigerant handling
Chlorine
Safety group (ASHRAE)
Molecular weight
Boiling point (-F)
Steam pressure [77-F](PSIG)
Saturated steam density [77-F](lb/ft3)
Combustibility
ODP w1
GWP w2
Refrigerant charge method
Additional charge on leakage
Kind
Color
Smell
w1:Ozone Depletion Potential : based on CFC-11
w2 :Global Warming Potential : based on CO2
OB444C--1.qxp 07.10.18 2:17 PM Page 3

4
R410A tools Can R22 tools be used?
Gas leak detector
R410A has high pressures beyond the measurement range of existing
gauges.
Hose material has been changed to improve the pressure resistance.
Dedicated for HFC refrigerant.
1/4in. and 3/8in.
Description
Clamp bar hole has been enlarged to reinforce the spring strength in the tool.
Provided for flaring work (to be used with R22 flare tool).
Provided to prevent the back flow of oil.This adapter enables you to use
vacuum pumps.
It is difficult to measure R410A with a charging cylinder because the
refrigerant bubbles due to high pressure and high-speed vaporization.
No
No
No
Yes
Yes
New
New
New
Gauge manifold
Charge hose
Torque wrench
Flare tool
Flare gauge
Vacuum pump
adapter
Electronic scale for
refrigerant charging
No : Not Substitutable for R410A Yes : Substitutable for R410A
No 1/2in. and 5/8in.
1.Tools dedicated for the air conditioner with R410A refrigerant
The following tools are required for R410A refrigerant. Some R22 tools can be substituted for R410A tools.
New Specification Current Specification
The incompatible refrigeration oil easily separates from
refrigerant and is in the upper layer inside the suction muffler.
Raising position of the oil back hole enables to back the
refrigeration oil of the upper layer to flow back to the
compressor.
Since refrigerant and refrigeration oil are compatible,
refrigeration oil goes back to the compressor through the
lower position oil back hole.
Compressor
Suction muffler
Oil back hole
Refrigeration oil
Refrigerant
Compressor
Suction muffler
Oil back hole
Refrigeration oil /Refrigerant
Compressor
-22 -4 14 32 50 68 86 104 122 140
-73
0
73
145
218
290
363
435
508
580
(PSIG)
R410A
R22
Conversion chart of refrigerant temperature and pressure
Saturated liquid pressure
(-F)
OB444C--1.qxp 07.10.18 2:17 PM Page 4

5
R410A
Pipe diameter
(inch)
1/4
3/8
1/2
5/8
17 [11/16]
22 [7/8]
26 [1-1/32]
29 [1-5/32]
Dimension of flare nut
R22
(mm) [inch]
17 [11/16]
22 [7/8]
24 [15/16]
27 [1-1/16]
2Flaring work and flare nut
Flaring work for R410A pipe differs from that for R22 pipe.
For details of flaring work, refer to installation manual “FLARING WORK”.
3.Refrigeration oil
Apply the special refrigeration oil (accessories: packed with indoor unit) to the flare and the union seat surfaces.
4.Air purge
•Do not discharge the refrigerant into the atmosphere.
Take care not to discharge refrigerant into the atmosphere during installation, reinstallation, or repairs to the refrigerant
circuit.
•Use the vacuum pump for air purging for the purpose of environmental protection.
5.Additional charge
For additional charging, charge the refrigerant from liquid phase of the gas cylinder.
If the refrigerant is charged from the gas phase, composition change may occur in the refrigerant inside the cylinder and the
outdoor unit. In this case, ability of the refrigeration cycle decreases or normal operation can be impossible. However,
charging the liquid refrigerant all at once may cause the compressor to be locked. Thus, charge the refrigerant slowly.
2.Refrigerant piping
1Specifications
Use the copper or copper-alloy seamless pipes for refrigerant that meet the following specifications.
Wall thickness
(inch)
Outside diameter
(inch)
1/4
3/8
1/2
5/8
0.0315
0.0315
0.0315
0.0394
Heat resisting foam plastic
Specific gravity 0.045 Thickness 0.315 inch
Insulation material
Electronic scale for refrigerant charging
Outdoor unit
Refrigerant gas
cylinder
operating valve
Refrigerant gas cylinder
for R410A with siphon
Refrigerant (liquid)
Service port
Gauge manifold
valve (for R410A)
Union
Liquid pipe
Gas pipe
Stop valve
Indoor unit
Charge hose (for R410A)
OB444C--1.qxp 07.10.18 2:17 PM Page 5

6
MXZ-3A30NA
Air inlet
Drain outlet
(Back and side)
Air outlet
Air inlet
Drain outlet
(Back and side)
Air outlet
MXZ-3A30NA - MXZ-4A36NA
1
Air outlet
Drain outlet
Air inlet
(Back and side)
OB444C--1.qxp 07.10.18 2:17 PM Page 6

7
1
09
12
15
09+09
09+12
09+15
12+12
95
95
95
97
97
97
97
3.34
4.53
7.05
7.80
9.64
9.64
9.64
3.69
5.01
7.79
8.62
10.66
10.66
10.66
–
–
–
9,000
11,500
12,500
10,000
9,000
(5,400 ~ 9,000)
12,000
(5,400 ~ 12,000)
15,000
(5,400 ~ 15,000)
18,000
(7,800 ~ 18,000)
20,000
(7,800 ~ 20,000)
20,000
(7,800 ~ 20,000)
20,000
(7,800 ~ 20,000)
730
(490 ~ 730)
990
( 490 ~ 990)
1,540
(490 ~ 1,540)
1,740
(630 ~ 1,740)
2,150
(630 ~ 2,150)
2,150
(630 ~ 2,150)
2,150
(630 ~ 2,150)
9,000
12,000
15,000
9,000
8,500
7,500
10,000
Indoor units
combination Unit A Unit B
Cooling capacity (BTU/h)
Total Power consumption
(W) Current
(A) Power factor
(%)
208V 230V
MXZ-2A20NA MXZ-2A20NA -
09
12
15
09+09
09+12
09+15
12+12
95
95
95
97
97
97
97
4.30
5.40
7.87
8.16
7.98
7.98
7.98
4.76
5.97
8.70
9.02
8.82
8.82
8.82
–
–
–
10,900
12,500
13,750
11,000
10,900
(5,200 ~ 15,400)
13,600
(5,200 ~ 16,400)
18,000
(5,200 ~ 21,100)
21,800
(8,500 ~ 21,800)
22,000
(8,500 ~ 22,000)
22,000
(8,500 ~ 22,000)
22,000
(8,500 ~ 22,000)
940
(480 ~ 1,430)
1,180
(480 ~1,460)
1,720
(480 ~ 2,100)
1,820
(520 ~ 1,820)
1,780
(520 ~ 1,780)
1,780
(520 ~ 1,780)
1,780
(520 ~ 1,780)
10,900
13,600
18,000
10,900
9,500
8,250
11,000
Indoor units
combination
Heating capacity (BTU/h)
Total Power consumption
(W) Current
(A) Power factor
(%)
208V 230V
Unit A Unit B
OB444C--1.qxp 07.10.18 2:17 PM Page 7
INDOOR UNIT OPERATIONAL CHARACTERISTICS
The following charts show indoor unit performance when operating individually or in combination. For authorized system
configurations of the indoor units, please refer to the Mr. Slim brochure.
3

8
1
09
12
15
17
24
09+09
09+12
09+15
09+17
09+24
12+12
12+15
12+17
15+15
15+17
17+17
09+09+09
09+09+12
09+09+15
09+09+17
95
95
95
95
95
97
97
97
97
97
97
97
97
97
97
97
97
97
97
97
3.66
4.58
6.04
6.77
10.07
8.07
8.96
11.21
12.10
14.34
11.21
12.55
12.55
12.55
12.55
12.55
12.82
14.57
14.57
14.57
4.05
5.06
6.68
7.49
11.13
8.92
9.91
12.39
13.38
15.86
12.39
13.88
13.88
13.88
13.88
13.88
14.18
16.11
16.11
16.11
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
9,000
11,400
12,900
13,800
9,000
(7,200 ~ 9,000)
12,000
(7,200 ~ 12,000)
15,000
(7,200 ~ 15,000)
16,200
(7,200 ~ 16,200)
22,000
(7,200 ~ 22,000)
18,000
(12,000 ~ 18,000)
21,000
(12,000 ~ 21,000)
24,000
(12,000 ~ 24,000)
25,200
(12,000 ~ 25,200)
28,000
(12,000 ~ 28,000)
24,000
(12,000 ~ 24,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
27,000
(12,600 ~ 27,000)
28,400
(12,600 ~ 28,400)
28,400
(12,600 ~ 28,400)
28,400
(12,600 ~ 28,400)
–
–
–
–
–
9,000
12,000
15,000
16,200
20,400
12,000
14,500
15,200
13,000
13,800
13,000
9,000
8,500
7,750
7,300
9,000
12,000
15,000
16,200
22,000
9,000
9,000
9,000
9,000
7,600
12,000
11,500
10,800
13,000
12,200
13,000
9,000
8,500
7,750
7,300
Indoor units
combination Unit A Unit B Unit C
Cooling capacity (BTU/h)
Total Power consumption
(W) Current
(A) Power factor
(%)
208V 230V
MXZ-3A30NA MXZ-3A30NA -
800
(650 ~ 800)
1,000
(650 ~ 1,000)
1,320
(650 ~ 1,320)
1,480
(650 ~ 1,480)
2,220
(650 ~ 2,200)
1,800
(920 ~ 1,800)
2,000
(920 ~ 2,000)
2,500
(920 ~ 2,500)
2,700
(920 ~ 2,700)
3,200
(920 ~ 3,200)
2,500
(920 ~ 2,500)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,860
(1,000 ~ 2,850)
3,250
(1,000 ~ 3,250)
3,250
(1,000 ~ 3,250)
3,250
(1,000 ~ 3,250)
OB444C--1.qxp 07.10.18 2:17 PM Page 8

9
09
12
15
17
24
09+09
09+12
09+15
09+17
09+24
12+12
12+15
12+17
15+15
15+17
17+17
09+09+09
09+09+12
09+09+15
09+09+17
95
95
95
95
95
97
97
97
97
97
97
97
97
97
97
97
97
97
97
97
5.03
6.32
8.88
10.25
11.53
7.62
8.87
9.86
9.86
8.87
9.86
9.68
9.59
9.50
9.46
9.41
9.77
9.77
9.77
9.77
5.57
6.98
9.82
11.34
12.75
8.43
9.81
10.90
10.90
9.81
10.90
10.71
10.61
10.51
10.46
10.41
10.80
10.80
10.80
10.80
Indoor units
combination Unit A Unit B Unit C
Heating capacity (BTU/h)
Total Power consumption
(W) Current
(A) Power factor
(%)
208V 230V
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
9,500
11,400
13,000
13,900
10,900
(8,600 ~ 15,400)
13,600
(8,600 ~ 16,400)
18,000
(8,600 ~ 21,100)
20,100
(8,600 ~ 21,500)
23,200
(8,600 ~ 27,800)
21,800
(11,000 ~ 31,000)
24,500
(11,000 ~ 33,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
27,000
(11,000 ~ 35,000)
28,500
(11,400 ~ 36,000)
28,600
(11,400 ~ 36,000)
28,600
(11,400 ~ 36,000)
28,600
(11,400 ~ 36,000)
–
–
–
–
–
10,900
13,600
16,900
17,700
19,700
13,500
15,000
15,800
13,500
14,300
13,500
9,500
8,600
7,800
7,350
1,100
(780 ~1,520)
1,380
(780 ~ 1,600)
1,940
(780 ~ 2,280)
2,240
(780 ~ 2,300)
2,520
(780 ~ 3,000)
1,700
(740 ~2,560)
1,980
(740 ~ 2,800)
2,200
(740 ~ 2,920)
2,200
(740 ~ 2,920)
1,980
(740 ~ 2,740)
2,200
(740 ~ 2,920)
2,160
(740 ~ 2,860)
2,140
(740 ~ 2,860)
2,120
(740 ~ 2,800)
2,110
(740 ~ 2,800)
2,100
(740 ~ 2,800)
2,180
(740 ~ 2,880)
2,180
(740 ~ 2,880)
2,180
(740 ~ 2,880)
2,180
(740 ~ 2,880)
10,900
13,600
18,000
20,100
23,200
10,900
10,900
10,100
9,300
7,300
13,500
12,000
11,200
13,500
12,700
13,500
9,500
8,600
7,800
7,350
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10
09
12
15
17
24
09+09
09+12
09+15
09+17
09+24
12+12
12+15
12+17
15+15
15+17
17+17
09+09+09
09+09+12
09+09+15
09+09+17
09+09+24
09+12+12
95
95
95
95
95
97
97
97
97
97
97
97
97
97
97
97
97
97
97
97
97
97
4.05
5.06
6.68
7.49
11.13
8.92
9.91
12.39
13.38
15.86
12.39
13.88
13.88
13.88
13.88
13.88
14.18
16.21
17.35
17.35
17.35
17.35
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
9,000
12,000
14,500
15,700
18,300
11,700
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
9,000
(7,200 ~ 9,000)
12,000
(7,200 ~ 12,000)
15,000
(7,200 ~ 15,000)
16,200
(7,200 ~ 16,200)
22,000
(7,200 ~ 22,000)
18,000
(12,000 ~ 18,000)
21,000
(12,000 ~ 21,000)
24,000
(12,000 ~ 24,000)
25,200
(12,000 ~ 25,200)
28,000
(12,000 ~ 28,000)
24,000
(12,000 ~ 24,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
26,000
(12,000 ~ 26,000)
27,000
(12,600 ~ 27,000)
30,000
(12,600 ~ 30,000)
32,100
(12,600 ~ 32,100)
32,100
(12,600 ~ 32,100)
32,100
(12,600 ~ 32,100)
32,100
(12,600 ~ 32,100)
–
–
–
–
–
9,000
12,000
15,000
16,200
20,400
12,000
14,500
15,200
13,000
13,800
13,000
9,000
9,000
8,800
8,200
6,900
11,700
9,000
12,000
15,000
16,200
22,000
9,000
9,000
9,000
9,000
7,600
12,000
11,500
10,800
13,000
12,200
13,000
9,000
9,000
8,800
8,200
6,900
8,700
Indoor units
combination Unit A Unit B Unit C Unit D
Cooling capacity (BTU/h)
Total Power consumption
(W) Current
(A) Power factor
(%)
208V
MXZ-4A36NA 208V
800
(650 ~ 800)
1,000
(650 ~ 1,000)
1,320
(650 ~ 1,320)
1,480
(650 ~ 1,480)
2,200
(650 ~ 2,200)
1,800
(920 ~ 1,800)
2,000
(920 ~ 2,000)
2,500
(920 ~ 2,500)
2,700
(920 ~ 2,700)
3,200
(920 ~ 3,200)
2,500
(920 ~ 2,500)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,800
(920 ~ 2,800)
2,860
(1,000 ~ 2,850)
3,270
(1,000 ~ 3,270)
3,500
(1,000 ~ 3,500)
3,500
(1,000 ~ 3,500)
3,500
(1,000 ~ 3,500)
3,500
(1,000 ~ 3,500)
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