Lennox LNINVE052 Service Manual page 59

Decrease
frequency
17 F9
due to high
air discharge
DC busbar
18 voltage is PH
too high
Detection
malfunction
19 U5
of system
current
56
Flash
9 times
■
every 3s
Flash
11 times
□
every 3s
Flash
13 times
□
every 3s
All loads
operates
normally,
while
■ □ □
operation
frequency of
compressor
decreases.
During cooling
and drying
operation,
compressor
stops while
■ □ ☆
indoor fan
operates.
During heating
operation, all
loads stop.
During cooling
and drying
operation,
compressor
and outdoor
fan stop while
■ ☆ ■
indoor fan
operates.
During heating
operation, all
loads stop.
Service Manual
Overload; ambient
temperature is too 1. Reduce load;
high;
Refrigerant is not
2. Add refrigerant
enough
3. Replace
Malfunction electronic
of electronic expansion valve
expansion valve → replace outdoor
unit's main board
（EKV）
AP1
1. Measure the
voltage at position
L and N on wiring
board (XT). If the
voltage is higher 1. Check whether
than 265VAC, power supply
wait until the network is
power voltage is abnormal;
decreased within
normal range and
then turn on the
unit;
2. If AC input
is normal,
measure the
voltage between
A and B ends
of electrolytic
capacitor (fig. 30
2. Replace outdoor
in 9.1) on control
unit's main board
board (AP1)
AP1;
after turning on
the unit. If it's
normal, the circuit
has malfunction.
Please replace
the main board of
outdoor unit.
Malfunction of
circuit on outdoor
1. Replace outdoor
unit's main board
unit's main board
AP1. Replace
AP1
outdoor unit's
main board AP1.
Installation and Maintenance