Mitsubishi Electric PRH-P8MYA Technical & Service Manual page 74

(6) Press the "ON/OFF" button to reset the test run in progress
• The test run will be automatically shut down after two hours in response to the AUTO STOP setting of two hours
on the timer.
• During the test run, the room temperature display shows the unit indoor-side liquid piping temperatures.
• In the case of the test run, the OFF timer will activate, and the test run will automatically stop after two hours.
• The room temperature display section shows the control temperature for the units during the test run.
• Check that the units are running properly operation.
Malfunctions may not be displayed even if the wiring is incorrect.
(*1)
After turning ON the power, the system will go into startup mode, and the remote controller operation lamp (red) and
the room temperature display section's "H0" will flash. Also, in the case of the indoor-side controller board substrata
LEDs, LED 1 and LED 2 light up (when address is 0) or become dim (when address is not 0), and LED 3 flashes. In
the case of the outdoor-side controller board substrata LED 1 display,
1-second intervals.
• If one of the above operations does not function correctly, the following causes should be considered, and if
applicable, dealt with. (The following symptoms have been determined under test run mode. Note that "startup" in
the chart means the *1 display above.)
Remote Controller Display
Remote controller is displaying "H0", and operation
is not possible.
After power is turned ON, "H0" is displayed for 3
mins., then error code is displayed.
Power is turned ON, and "EE" or "EF" are displayed
after "H0" is displayed.
Display messages do not appear even when remote
controller operation switch is turned ON (operation
lamp does not light up).
Operation display appears but soon disappears even
when remote controller operations are executed.
* Press the remote controller's "CHECK" button twice consecutively to be able to run a self diagnosis. See the chart below for content of error code displays.
LCD Nonconformity Content
P1 Suction sensor error
P2 Piping (liquid pipe) sensor error
P4 Drain sensor error
P5 Drain overflow safeguard operation
P6 Freezing/overheating safeguard operation
See the chart below for details of the LED displays (LED 1, 2, 3) on the indoor-side controller board.
LED 1 (microcomputer power supply)
LED 2 (remote controller feed)
LED 3 (indoor and outdoor signals)
2. Outdoor-side controller board
(1) Check Items
• After installation of unit, and electric wiring work,check that the unit is free from leaks
connections,and incorrect polarity.
• Check that there is no negative phase and open phase. (The F1 message for negative phase and the F2 message
for open phase will flash at LED 1 on the outdoor-side controller board substrate. If this happens,rewire correctly.)
• Measure the impedance between power terminals (Single phase: L, N,
ground with a 500 V Megger and check that it is 1.0 M or more. Do not operate the equipment if measurement is
less than 1.0 M.
• When there is no error at the unit. (If there is an error at the unit, it can be evaluated at LED 1 [digital display]
of the outdoor-side controller board.)
• After checking the above, execute the test run in accordance with the following.
Symptoms
Outdoor Substrate LED Display
After "startup" display, "00" is dis-
played (correct operation).
After "startup" display, error code is
displayed.
After "startup" display, "F1" (negative
phase) is displayed.
After "startup" display, "00" or "EE" is
displayed ("EE" is displayed when a
test run is made).
After "startup" display, "EA" (error for
number of units) or "Eb" (unit number
error) is displayed.
After "startup" display, "00" is dis-
played (correct operation).
After "startup" display, "00" is dis-
played (correct operation).
After "startup" display, "00" is dis-
played (correct operation).
LCD
P8 Pipe temperature error
P9 Piping (2-phase pipe) sensor error
U0 ~ UP Unit nonconformity
F1 ~ FA Unit nonconformity
E0 ~ E5 Signal error between remote controller and
unit
Displays the ON/OFF of power for control. Check that this is lit during normal use.
Displays the ON/OFF of feed to wired remote controller. Is only lit for the unit of outdoor-side controller board with address "00".
Displays signal between indoor-side and outdoor-side controller boards. Check that this is flashing during normal use.
and
–
• After power is turned ON, system startup lasts for about 2 mins., and "H0"
is displayed (correct operation).
• Outdoor-side unit's safeguard installation connector is open.
• Negative phase and open phase of outdoor unit's power terminal board
(Single phase: L, N,
• Incorrect connection of outdoor terminal board (Single phase: L, N,
triple phase: L1, L2, L3, N,
• Unit construction differ
• Wiring for the unit is not connected correctly. (Polarity is wrong for S1, S2,
S3)
• Remote controller transmission wire short
• There is no unit for address 0 (address is something other than 0).
• Remote controller transmission wire burnout
• After cancellation of function selection, operation is not possible for about
30 secs. (correct operation).
Nonconformity Content
E6 ~ EF
FFFF
/triple phase: L1, L2, L3, N,
- 71 -
are displayed alternatively at
–
Cause
/triple phase: L1, L2, L3, N, )
grounding and S1, S2, S3)
LCD Nonconformity Content
Signal error between indoor-side controller
board and outdoor-side controller board
- - - - No error history
No relevant unit
of refrigerant, loosened
/
) and the