Mitsubishi Electric LGH-F300RX3-E Handbook page 20

Symptom
No.
5 Supply air fan periodical-
ly stops operating.
6 Takes in air from out-
doors during interlocked
operation with a Mr. Slim
or a City Multi, but supply
air fan doesn't stop oper-
ating when defrosting.
7 The supply air fan and
exhaust fan both periodi-
cally stop operating.
8 Fan speed will not
change.
9 Damper board does not
operate.
10 Operation monitor output
is late with regard to exter-
nal control input ON/OFF.
11 Operation monitor output
is OFF during operation.
12 Delayed start operation
does not work when
Delayed start is set.
13 Lossnay does not operate when
power is on even when the
power on/off setting is made.
14 Interlocked operation is
different from the set-
tings.
Cause
« When the outdoor air temperature is 14°F or
less, operation stops after a fixed period of
about 10 minutes to keep the Lossnay Core
from freezing. (Cold weather area spec)
« When connected to a Mr. Slim or a City Multi
by a duct, operation stops when the air condi-
tioner is defrosting.
« The indoor unit's outside air intake selection is
invalid.
« When connected to Mr. Slim or City Multi by a
duct and the function select switch (SW 5-3) on
the Lossnay circuit board is ON, operation
stops when the air conditioner is defrosting.
« The High/Low switching extermary input
(CN16) is set to ON.
« The function select switch (SW2-4.5) on the Lossnay cir-
cuit board is set to the high fixed or low fixed fan speed.
« The trial operation switch (SW2-1) is turned
ON.
« The outside air temperature is less than 46.4°F.
« The damper board operation is defective.
« The thermistor related connectors are not
securely connected.
« The damper related connectors are not secure-
ly connected.
« The trial operation switch (SW2-1 or SW2-3) is
turned ON.
« When using the remote controller to change
ventilation mode, there may be a delayed start
of up to 30 seconds depending on the timing.
« When using the PZ-41SLB-E there is a maxi-
mum delay of 7 seconds, or without using
there is a maximum delay of 3 seconds.
« When the function select switch (SW 5-2) on
the Lossnay circuit board is ON, for operation
monitor output for interlocked operation with
the supply air fan, it turns OFF when the out-
side air is 14°F or less or when the air condi-
tioner is defrosting.
« When using the PZ-41SLB-E, the circuit func-
tion select switch is set for delayed start.
« Using the PZ-41SLB-E.
« When using the PZ-41SLB-E, the circuit func-
tion select switch is set for interlocked opera-
tion.
— 20 —
Corrective action
« This is no error.
« This is no error.
« Set the outdoor air intake selec-
tion of a indoor unit to "ON."
« Check the function select switch
(SW5-3).
« Check the High/Low change
input (CN16).
« Check the function select switch
(SW2-4,5).
« Check the trial operation switch
(SW2-1).
« Check the outdoor air temperature.
« Remove the load and check or
move the damper board by hand.
« Check the connections of the
lead wire connectors and the cir-
cuit connectors.
« Check the connections of the
lead wire connectors and the
control circuit connectors.
« Check the trial operation switch
(SW2-1 or SW2-3).
« This is no error.
« This is no error.
« Check the function select switch
(SW5-2).
« Set delayed start at the remote con-
troller (the circuit board switch is not in
effect when using the PZ-41SLB-E).
« The power supply ON/OFF set-
ting is not in effect when using
PZ-41SLB-E.
« Set interlocked operation at the
remote controller (the circuit
board switch is not in effect when
using the PZ-41SLB-E).