Mitsubishi Electric PKH18FK1 Technical & Service Manual page 43

(1) Indoor coil temperature code
During the test run, the indoor coil temperature code from 1 to 15 is displayed on the remote controller instead of room
temperature. The code should fall with the lapse of time in normal COOL operation, and should rise in normal HEAT
operation.
Code
-40~34°F
Indoor coil temperature
Code
~113°F
Indoor coil temperature
(2) Trouble during test run
l If the unit malfunctions during the test run, refer to section 10 in this manual entitled "TROUBLESHOOTING."
l When the optional program timer is connected to the conditioner, refer to its operating instructions.
2-8 Emergency operation
When the remote controller or microprocessor malfunctions but all other parts are normal, emergency operation is started
by setting the dip switch SW3 on the indoor controller board.
<Before emergency operation>
1. Make sure the compressor and the indoor fan are operating normally.
2. Locate the defect with the self-diagnostic function. When the self-diagnostic function indicates "protective function is
working", release the protective function before starting the emergency operation.
CAUTION: When the self-diagnostic function indicates a check code of "P5" (drain pump malfunction), DO NOT start
the emergency operation because the drain may overflow.
<How to operate>
1. For emergency cooling, set the dip switch SW3-1 to ON and SW3-2 to OFF.
For emergency heating, set the dip switch SW3-1,2 to ON.
SW3 setting
emergency
heating
2 .3 .4 ON
2. Turn ON the outdoor unit breaker and then turn ON the indoor unit breaker.
Emergency operation will now start.
3. During emergency operation, the indoor fan operates on high speed, the auto vanes do not operate.
4. To stop emergency operation, turn OFF the indoor unit breaker.
5. Movements of the vanes do not work in emergency operation, therefore you have to slowly set them manually to the
appropriate position.
NOTE: The remote controller POWER ON/OFF button can not start/stop emergency operations.
CAUTION: Do not use emergency cooling for more than 10 hours, as the indoor coil may freeze.
1 2 3
~50°F ~59°F
9 10 11
~122°F ~131°F
emergency normal
cooling operation
1 .2 .3 ON 1 - 4 OFF
OC193-41
4 5
~68°F ~77°F ~86°F
12 13
~140°F ~158°F ~194°F
microprocessor board
6 7 8
~95°F ~104°F
14 15
Thermistor abnormality