Emergency / Test Operation - Mitsubishi Electric MSC-CA20VB Service Technical Manual

(4) Press HR. and MIN. button to set the timer. Time setting is 10-minute units.
HR. and MIN. button will work when "
These marks disappear in 1 minute.
After setting ON timer, check that OPERATION INDICATOR lamp of the indoor unit lights.
NOTE1 : Be sure to place the remote controller at the position where its signal can reach the air conditioner even during
TIMER operation, or the set time may deviate within the range of about 10 minutes.
NOTE2 : Reset the timer in the following cases, or the set time may deviate and other malfunctions may occur.
• A power failure occurs.
• The circuit breaker functions.
2. Cancel
TIMER setting can be cancelled with ON or OFF TIMER buttons. ("
To cancel ON timer, press "
To cancel OFF timer, press "
TIMER is cancelled and the display of set time disappears.
PROGRAM TIMER
• OFF timer and ON timer can be used in combination.
• " " and " " display shows the order of OFF timer and ON timer operation.
(Example 1) The current time is 8:00 PM.
The unit turns off at 11:00 PM, and on at 6:00 AM.
NOTE : TIMER setting will be cancelled by power failure or breaker functioning.

1-9. EMERGENCY / TEST OPERATION

In case of test run operation or emergency operation, use EMERGENCY OPERATION switch on the front of the
indoor unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of remote
controller run down. The unit will start and OPERATION INDICATOR lamp will light.
The first 30 minutes of operation is the test run operation. This operation is for servicing. The indoor fan speed runs at
High speed and the system is in continuous operation. (The thermostat is ON.)
After 30 minutes of test run operation, the system shifts to EMERGENCY COOL [/ HEAT<MUH-GA20/GA25/GA35VB>]
MODE with a set temperature of 24°C. The fan speed shifts to Med. speed.
The coil frost prevention works even in emergency operation [, and defrosting<MUH-GA20/GA25/GA35VB> too].
In the test run or emergency operation, the horizontal vane operates in VANE AUTO (
Emergency operation continues until EMERGENCY OPERATION switch is pressed once again
(MU-GA20/GA25/GA35VB, MUX-2A28/2A59/3A60/3A63/2A70/4A73VB)/once or twice (MUH-GA20/GA25/GA35VB) or the
unit receives any signal from the remote controller.
In case of latter, normal operation will start.
NOTE : Do not press EMERGENCY OPERATION switch during normal operation.
" button.
" button.
PM
AM
EMERGENCY OPERATION switch
" or " " mark is flashing.
(Example 2) The current time is 11:00 AM.
The unit turns on at 5:00 PM, and off at 9:00 PM.
• The following indication does not depend on the
shape of lamp.
Press once <Cool>
Press again <Heat>
Press once again <Stop>
w
Heat is available only in MUH-GA20/GA25/GA35VB.
13
" or " ")
PM
PM
) mode.
OPERATION INDICATOR lamp
Lighted
Not lighted