Lennox MPA009S4S Service Manual page 125

Error Code:
P6
Description: Inverter module (IPM) error.
General Note: When the voltage signal that IPM sends to the compressor drive chip is abnormal, the display LED will show "P6" and unit will turn
off.
P6
Check whether the voltage range
of P-N on IPM module is normal?
277-356VDC for 18-30KBtu/h; 277-
410VDC for 36KBtu/h
Check whether the connecting
wiring between main board and the
IPM module is connected tightly.
Check whether the connecting wiring
to the compressor is connected cor-
rectly and tightly
Replace the IPM
module, check
whether the system
works normally.
Check if the outdoor
fan runs properly
or the outdoor unit
ventilation is good.
Replace the main board;
check whether the sys-
tem operates normally?
Yes
Replace the compressor,
check whether the sys-
tem operates normally?
Yes
Connect it
No
tightly, unit oper-
ates correctly?
Yes
No
tightly, check ok
Yes
No
No
For AC fan models,
check whether the
resistance of the fan
motor is normal. If not,
Yes
replace the fan motor.
For DC fan models, re-
fer to the solution of fan
speed malfunction (E8)
No
. Find out the cause
and repair it.
Yes
No
Yes
Check whether the
No
input power supply is
correct? 208-230V,
1PH, 60Hz
Check whether the
power supply line is
connected correctly
and tightly.
Connect it
Check whether
the lines in E-part
or not?
box are connected
tightly.
Check whether the bridge rectifi-
ers are normal? Use the multi-
meter to measure the resistance
between each two terminals,
check whether there is the condi-
tion that value of resistance is 0.
Yes
Problem Solved
125
Correct the incoming
power problem, then
No
check whether the sys-
tem operates normally
No
Yes
Connect it cor-
No
rectly and tightly,
check ok or not?
Yes No
No
Connect it tightly,
check ok or not?
Yes No
Yes
bridge rectifiers.
Check whether the wir-
ing of each reactor is
correct? Check whether
the PFC module broken.
wiring or reactor
or replace the
PFC module(for
36HRFN1-M)
No
Replace the
No
Replace the
M4OC-