For Movement And Maintenance - Mitsubishi Electric MS12 Installation Manual

MSH type
•
Before performing the test run, recheck any wrong wiring.
Wrong wiring prevents normal operation or results in blown fuse disabling
operation.
•
The test run can be started by pressing EMERGENCY OPERATION switch. When
the EMERGENCY OPERATION switch is once pressed, the unit will start the test
run (continuous operation) for 30 minutes.
A thermostat does not work during this time. After 30 minutes the unit will start the
EMERGENCY OPERATION at a fixed temperature setting of 75 °F in COOL
MODE or HEAT MODE.
•
Perform test run in the following procedure.
PROCEDURE
•
Press the EMERGENCY OPERATION switch.
1 Press it once, and after test run for 30 minutes the EMERGENCY COOL MODE starts.
If the left side lamp of the operation indicator blinks every 0.5 seconds, inspect the
indoor/outdoor connecting wire A for mis-wiring.
2 Press it once more, and the EMERGENCY HEAT MODE starts.
3 Press it once more, and the operation stops.
(The operation mode changes in order of 1 ~ 3 every time the EMERGENCY
OPERATION switch is pressed.)
Mode Operation Indicator lamp
1 COOL
(Light) (Off)
2 HEAT
(Off) (Light)
3 STOP
(Off) (Off)
•
In starting the heating operation, indoor unit fan may not operate to prevent
blowing cool air. Please wait for a few minutes until the temperature of heat
exchanger rises and warm air blows out.
MS type and MSH type
Checking the remote (infrared) signal reception
Press the ON/OFF button on the remote controller and check that an electronic
sound is heard from the indoor unit. Press the ON/OFF button again to turn the
air conditioner off.
Checking the auto restart function
After operating the unit with the remote controller, turn off the main power. Then
turn it on again and check if the unit operates in the same mode as the mode
right before the main power shutoff.
If the indoor unit is operated with the remote controller, both the
test run and the emergency operation are released by commands
from the remote controller.
•
Once the compressor stops, the restart preventive device operates so the
compressor will not operate for three minutes to protect the air conditioner.
6-5 EXPLANATION TO THE CUSTOMER
•
Using the OPERATING INSTRUCTIONS, explain the following to the customer,
how to control temperature, how to remove the air filters, how to remove or put the
remote controller in the remote controller mounting hardware, how to clean,
precautions for operation, etc.
•
Recommend the customer to read the OPERATING INSTRUCTIONS carefully.

7. FOR MOVEMENT AND MAINTENANCE

7-1 REMOVING AND REINSTALLING THE FRONT PANEL
FRONT PANEL REMOVAL
4 Release the hooks.
1 Remove the screw caps.
2 Remove three screws.
3 Pull the bottom.
FRONT PANEL REINSTALLATION
1 Before installing the panel, set the horizontal vane to the position as shown in the
2 Attach the bottom of the panel under the horizontal vane.
3 Set the top of the panel.
4 Push as the arrow mark on the panel to fix it to the air conditioner.
EMERGENCY
7-2 REMOVING THE INDOOR UNIT
OPERATION switch
Remove the bottom of the indoor unit from the installation plate.
1 Remove the front panel. (See FRONT PANEL REMOVAL shown above.)
2 Insert flat screwdrivers into the square holes at the left and right bottom of the
indoor unit and push them up; the bottom of the indoor unit goes down and the
hooks are released.
7-3 GAS CHARGE
1 Connect gas cylinder to the service port of stop valve (3-way).
2 Perform air purge of the pipe (or hose) coming from refrigerant gas cylinder.
3 Replenish specified amount of the refrigerant, while operating the air conditioner
Never charge liquid refrigerant, such as by inverting the gas cylinder while
charging, otherwise troubles may be generated.
To maintain the high pressure of the gas cylinder, warm the gas cylinder with warm
water (under 106 °F) during cold season. But never use naked flame or steam.
Hold this concave section and pull
the bottom forward to remove the
front panel.
HEAD OFFICE: MITSUBISHI DENKI BLDG., 2-2-3, MARUNOUCHI, CHIYODA-KU,
TOKYO 100-8310, JAPAN
figure below.
1 Horizontal vane
Slightly downward
Horizontal vane
Square hole
for cooling.
CAUTION
Union
Indoor
unit
Refrigerant gas cylinder
operating valve
Refrigerant gas cylinder
(R-22 gas) Gas charge
SCALE
3
2
Push
Go down
Stop valve
Liquid pipe
Outdoor
Gas pipe
unit
Service port
Charge hose