Service Manual

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No. Problem Factor Corrective action
10
Even though the
remote controller is
operated to change
the ventilation mode,
the ventilation mode
is not changed.
The outdoor temperature is
46.4°F (8°C) or lower.
When the outdoor temperature is 46.4°F (8°C)
or lower, the ventilation mode is fixed to the Heat
recovery mode.
The signal is input to the
Bypass mode switching input
(CN26 [1] [2]).
Check the Bypass mode switching input (CN26
[1] [2]). (See the Lossnay Operating/Installation
Instructions or PZ-62DR-E Instruction Book.)
The Lossnay unit is performing
the Night-purge operation.
When PZ-62DR-EA is used, The ventilation
mode cannot be changed during the Night-purge
operation. (See the Lossnay Operating/Installation
Instructions or PZ-62DR-E Instruction Book.)
The pre-heater is ON, or within
one hour after the pre-heater
is turned OFF.
When the pre-heater is ON, or for one hour after
the pre-heater is turned OFF, the ventilation mode
is fixed to the Heat recovery mode.
11 The ventilation
mode cannot be
switched when
Lossnay is operat-
ing in the automatic
mode.
Temperature condition for
Heat recovery mode or Bypass
mode is not satisfied.
Check the temperature map.
For details, see the Lossnay Operating/Installation
Instructions or PZ-62DR-E Instruction Book.
It has not passed 30 minutes since
the ventilation mode is switched.
Switching of the ventilation mode is controlled in 30
minutes cycle.
The outdoor temperature is
46.4°F (8°C) or lower.
When the outdoor temperature is 46.4°F (8°C)
or lower, the ventilation mode is fixed to the Heat
recovery mode.
The signal is input to the
Bypass mode switching input
(CN26 [1] [2]).
Check the Bypass mode switching input (CN26
[1] [2]). (See the Lossnay Operating/Installation
Instructions or PZ-62DR-E Instruction Book.)
The operation mode of the
interlocked air conditioner (Mr.
Slim indoor unit or City Multi
indoor unit) is set to fan opera-
tion or heating.
If the operation mode of the interlocked air condi-
tioner is fan operation or heating, the ventilation
mode of Lossnay is fixed to the Heat recovery
mode.
The pre-heater is ON, or within
one hour after the pre-heater
is turned OFF.
When the pre-heater is ON, or for one hour after
the pre-heater is turned OFF, the ventilation mode
is fixed to the Heat recovery mode.
12 Air volume is too
small.
Is the air filter clogged? Clean the air filter.
Pressure loss in the duct is too
high.
Set the supply/exhaust fan power up setting.
(See the Lossnay Operating/Installation
Instructions or PZ-62DR-E Instruction Book.)
The model selection switch
(SW6) is not set correctly after
the circuit board is replaced.
Make the SW6 setting appropriate for the model.
( See Chapter 8. (8) Setting status record (page
52).)
The indoor negative pressure
setting or the indoor positive
pressure setting is set.
Check the function selection switches (SW2-4 and
SW2-5) on the circuit board or the function settings
(No. 6 and 7) of PZ-62DR-EA.
(See the Lossnay Operating/Installation
Instructions or PZ-62DR-E Instruction Book.)
Power supply voltage is low. Check the power supply voltage.
In interlock with the air condi-
tioner, the outdoor air intake
port of the Lossnay unit is con-
nected with the air conditioner
by using a duct.
In this case, even if the Lossnay remote controller
is operated to start Lossnay while the air condi-
tioner is stopped, Lossnay will not supply air.
Airflow setting is performed
with PZ-62DR-EA.
Check the “Airflow” screen or the function settings
(No. 73 to 78, 87, and 88) of PZ-62DR-EA.
(See the Lossnay Operating/Installation
Instructions or PZ-62DR-E Instruction Book.)