Mitsubishi Electric Mr. Slim MVZ Series User manual

SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
SERVICE MANUAL
Model name
<Indoor unit>
Model name
<Indoor unit>
Series MVZ
2015
MVZ-A12AA4
MVZ-A30AA4
MVZ-A36AA4
MVZ-A18AA4
MVZ-A24AA4
INDOOR UNIT
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CONTENTS
1. SAFETY PRECAUTION 2
2. PART NAMES AND FUNCTIONS 3
3. SPECIFICATION 4
4. FAN PERFORMANCE AND CORRECTED AIR FLOW 6
5. SOUND PRESSURE LEVELS 12
6. OUTLINES & DIMENSIONS 15
7. WIRING DIAGRAM 17
8. REFRIGERANT SYSTEM DIAGRAM 18
9. HEATER CONTROL 19
1 . HUMIDIFIER CONTROL 22
11.ERV (ENERGY RECOVERY VENTILATION) CONTROL 23
12. TROUBLESHOOTING 24
13. DISASSEMBLY PROCEDURE 37
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2
SAFETY PRECAUTION
1
1-1. ALWAYS OBSERVE FOR SAFETY
Cautions for units utilising refrigerant R410A
Use new refrigerant pipes.
Make sure that the inside and outside of refrige-
rant piping is clean and it has no contamination
such as sulfur hazardous for use, oxides, dirt,
shaving particles, etc.
In addition, use pipes with specified thickness.
Store the piping to be used indoors during
installation and both ends of the piping sealed
until just before brazing. (Leave elbow joints, etc.
in their packaging.)
Use ester oil, ether oil or alkylbenzene oil (small
amount) as the refrigerant oil applied to flares
and flange connections.
In case of using the existing pipes for R22, be careful with
the followings.
·For A36 and A42, be sure to perform replacement oper-
ation before test run.
·Change flare nut to the one provided with this product.
Use a newly flared pipe.
·Avoid using thin pipes.
Charge refrigerant from liquid phase of gas
cylinder.
If the refrigerant is charged from gas phase, composition
change may occur in refrigerant and the efficiency will be
lowered.
Do not use refrigerant other than R410A.
If other refrigerant (R22 etc.) is used, chlorine in refrige-
rant can cause deterioration of refrigerant oil etc.
Use a vacuum pump with a reverse flow check
valve.
Vacuum pump oil may flow back into refrigerant cycle and
that can cause deterioration of refrigerant oil etc.
Use the following tools specifically designed for
use with R410A refrigerant.
The following tools are necessary to use R410A refrigerant.
Handle tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
Do not use a charging cylinder.
If a charging cylinder is used, the composition of refrigera-
nt will change and the efficiency will be lowered.
Flare tool
Electronic refrigerant
charging scale
Vacuum pump adaptor
Size adjustment 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.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
[1] Cautions for service
(1) Perform service after recovering the refrigerant left in unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.
(4) When performing service, install a filter drier simultaneously.
Be sure to use a filter drier for new refrigerant.
[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.)
Before obtaining access to terminal, all supply
circuits must be disconnected.
1-2. CAUTIONS RELATED TO NEW REFRIGERANT
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3
Gravimeter
Unit
[3] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
No. Tool name Specifications
1Gauge manifold ·Only for R410A
·Use the existing fitting specifications. (UNF1/2)
·Use high-tension side pressure of 5.3MPa·G or over.
2Charge hose ·Only for R410A
·Use pressure performance of 5.09MPa·G or over.
3Electronic scale
4Gas leak detector ·Use the detector for R134a, R407C or R410A.
5Adaptor for reverse flow check ·Attach on vacuum pump.
6Refrigerant charge base
7Refrigerant cylinder ·Only for R410A ·Top of cylinder (Pink)
·Cylinder with syphon
8Refrigerant recovery equipment
PART NAMES AND FUNCTIONS
2
•Indoor Unit
Air inlet
Air outlet
Air
inlet Air
outlet
(1)Vertical (2)Horizontal Right
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