MXZ-SM36NAMHZ Service Manual

ManualsBrandsMitsubishi ManualsCoolingWall Mounted 4-Zone H2i System - 36,000 BTU Outdoor - 9k + 9k + 9k + 15k Indoor - 23.0 SEER

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OCH789

Switch

Step

Function

Operation in Each Switch Setting

Remarks Purpose Additional Information

ON OFF When to Set

SWU1

ones digit

SWU2

tens digit

Rotary switch

Before turning

the power ON

— —

SW1

Digital

Display

Switch

1–8

Can be set either during

operation or not.

— —

SW2

Function

Switch

1 Selects operating system startup

With centralized

controller

Without centralized

controller

Before turning

the power ON

Turn ON when the centralized controller is

connected to the outdoor unit.

SW2-1 must be turned ON if a central controller

is connected to the system. An example of this

would be a TC-24, EW-50A, AG150, AE50 or

AE200. If SW2-1 is not turned on, while using

a central controller, in rare circumstances

problems may be encountered such as indoor

units not responding to group commands.

Therefore, turning SW2-1 ON is recommended

if a central controller is used.

Connection Information Clear Switch

Clear Do not clear

When relocating units or connecting additional units.

—

3 Abnormal data clear switch input

Clear

abnormal data

Normal

OFF to ON any time after

the power is turned on.

To delete an error history.

4 Pump down ON OFF

During compressor

running

To facilitate outdoor unit the pumping down operation.

Frequency = Fixed to 65 Hz

Indoor-linear expansion valve = Fully open

Outdoor fan step = Fixed to 10

Please refer to a section referring to the pumping

down on outdoor units Installation Manuals.

It might not be possible to collect all the refrigerant

if the amount is excessive.

5 Connect branch box Connect Not connect

Before the power

is turned ON.

OFF

— —

6 — — — — — — —

SW4/

SW8/

(SW9)

Model

Switch

1–6

MODEL SELECTION 1:ON 0:OFF

Before the power

is turned ON.

Set for each capacity.

— —

SW3 Trial

operation

1 ON/OFF from outdoor unit ON OFF

Any time after the

power is turned ON.

— —

2 Mode setting Heating Cooling — —

SW5

Function

switch

1 — — —

Can be set when

o󰀨 or during

operation

— —

Change the indoor unit's LEV

opening at startup

Enable Normal

To set the LEV opening at startup higher than usual.

(+150 pulses)

To improve the operation with the LEV almost clogged.

The refrigerant ow noise at start-

up become louder.

3 — — — — —

4 Auxiliary heater Enable Disable

Before the power

is turned ON.

Turn ON when an auxiliary heater is connected. (It

transmits a connection permission signal of the auxiliary

heater to the connected CITY MULTI indoor unit.)

Turn ON only when the auxiliary

heater is connected and operated.

Change the indoor unit's LEV

opening at defrost

Enable Normal

Can be set when

OFF or during

operation

To set the LEV opening higher than usual

during defrosting operation.

(Only Qj

[

10 is valid, + 300 pulses)

To avoid the discharge temperature increase

and provide efcient defrosting operation.

The refrigerant ow noise during

the defrosting operation becomes

louder.

Switching the target sub cool

(Heating mode)

Enable Normal

To decrease the target sub cool value.

To reduce the discharge temperature

decrease due to refrigerant liquid

accumulation in the units.

A refrigerant ow noise might be

generated if the sub cool value is

too small.

Switch

Step

Function

Operation in Each Switch Setting

Remarks Purpose Additional Information

ON OFF When to Set

SW5

Function

switch

During the outdoor unit is in HEAT

operation, additionally increase about 50

to 70 pulses of the LEV opening on the

indoor unit which is in FAN, STOP, COOL

or thermo-OFF

Active Inactive

Can be set when

OFF or during

operation

To additionally increase about 50 to 70 pulses of the LEV

opening for units other than in HEAT operation. To avoid

a refrigerant shortage (less capacity) due to refrigerant

liquid accumulation in the units which is not in operation.

A refrigerant ow noise might be generated

in units other than the one in operation.

8 During the outdoor unit is in operation,

fully closing the linear expansion valve

on the indoor unit which is in FAN or

COOL.*

Enable Normal

Before turning the

power ON.

To reduce the room temperature increase by setting

the LEV opening lower for the units in thermo-OFF

operation.

The refrigerant is more likely to collect in the units with

thermo-OFF operation, and causing the units refrigerant

shortage. (Results in less capacity and increase of

discharge temperature.)

SW6

Function

switch

1 — — — —

— —

2 — — — — — —

3 — — — — — —

4 Change of defrosting control

Enable

(For high

humidity)

Normal

Can be set

when OFF

or during

operation

To shorten the defrosting prohibition time in high

humidity (or heavy snow) region, in order to reduce

malfunctions caused by frost .

The performance of the HEAT operation is somewhat

reduced since the defrosting operation is frequently

performed.

5 — — —

— —

Switching the target discharge

pressure (Pdm)

Enable Normal

To raise the performance by setting the Pdm higher

during HEAT operation.

Power consumption is raised due to a higher frequency. (The

performance would not be raise at the maximum operating frequency.)

Switching (1) the target evaporation

temperature (ETm)

Enable Normal

To raise/reduce the performance by changing the target ETm during COOL

operation.

Switch to raise the performance: raises the performance

Switch to reduce the performance: prevents dew condensation

Switching it to raise the performance, it raises the power

consumption, and produces more dew condensation.

Switching it to reduce the performance, it makes the

performance insufcient.

Switching (2) the target evaporation

temperature (ETm)

Enable Normal

SW7

Function

switch

Ignore current sensor

abnormality and rotational

frequency abnormality of

outdoor fan motor

Enable Normal

After turning

the power ON

To perform a test run for electrical parts alone

without running the compressor. Also, to perform the

troubleshooting of electrical parts without operating

the outdoor unit’s fan.

Make sure to connect the connectors to the

compressor after checking the electrical parts. Be

careful not to get electrical shock while working on

electrical parts.

Setting to energize the freeze

stat heater (optional part)

During

heating

operation

only

Include

when the

heating

operation is

OFF.

Can be set when

OFF or during

operation

It reduces snow on the base, even it blows inside the

unit, by setting the base heater ON while the HEAT

operation is stopped.

Power consumption raises while the operation is

stopped.

High heating performance mode

(except for NAMHZ model)

Enable Normal Anytime

To raise the performance of HEAT

operation if it is insu󰀩cient.

The performance may not be raised depending on the capacity

of indoor units in operation, or outside air temperature.

Maximum frequency down at 1

hour after COOL operation

Enable Normal

Can be set when

OFF or during

operation

To reduce dew condensation on the indoor unit by

lowering the frequency.

The performance might be insufcient.

Simultaneous cooling and

heating with external heater

Enable Disable Anytime

The simultaneous operation of cooling and

heating will be possible by installing an external

heater to the CITY MULTI indoor unit.

For the installation of external heater and

the indoor unit setting, refer to the indoor

unit service manual.

6 Manual defrost

Manual

defrost

Normal

During compressor

running in HEAT

mode.

Turn ON when it is necessary to perform the defrosting

operation forcedly.

(

Effective only at startup, or 10

minutes after the last defrosting operation)

It performs the defrosting operation forcedly.

(HEAT operation is stopped temporarily.)

SW9

Function

Switch

Auto change over from remote

controller (IC with the minimum address)

Enable Disable

Before turning the

power ON

Enables the indoor unit with the minimum address

to select AUTO mode, and switches the operation

mode of the other indoor units to the same mode.

Cannot be set when the centralized control

is ON.

Switching the Silent/ Demand

mode

Demand

control

Silent

mode

Can be set when

OFF or during

operation

—

About the Silent mode/Demand control setting, refer to

"8-6. OUTDOOR UNIT INPUT/OUTPUT CONNECTOR".

— *

— —

— — —

SW5-7 Opens the indoor-

linear

expansion valve as a countermeasure against the indoor unit in FAN, COOL, STOP, or thermo-OFF operation with refrigerant-shortage status due to an accumulation of liquid refrigerant in the indoor unit.

SW5-8 Countermeasure against room temperature rise for indoor unit in FAN and COOL mode.

During heating operation and the ambient temperature is 39

°F (

°C)

or below, the freeze prevention heater is energized.

During heating mode is OFF (include thermo-OFF in cooling mode), and the ambient temperature is 39

°F (

°C)

or below, the freeze prevention heater is energized.

5 Use it for Model Switch. ((H)P36/48)

SW6-6 OFF ON

Target Pdm (kg/cm²)

31.5 33.5

SW6-7 OFF ON OFF ON

SW6-8 OFF OFF ON ON

Target ETm (°F(°C)) 48(9) 52(11) 43(6)

57(14)

OFF

2 3 4 5 6 7 8

OFF

2 3 4 5 6 7 8

OFF

2 3 4 5 6

OFF

2 3 4