Toshiba MMC-UP0151HP-E Service Manual Download

Page: 73 / 295

No.

Item

Refrigerant (Oil)
recovery control in
heating operation

Outline of specifications

Indoor units during stop/thermostat OFF or FAN
operation perform following controls when a refrigerant
(compressor oil) recovery signal is received from
outdoor unit at the heating operation,

(1) Opening the indoor unit PMV at constant valve

opening. (For a maximum of about 20 minutes)

(2) TC2 temperature is detected to close its PMV.

Also, the fan, louvers, drain pump may operate for
about one minute after recovery control finished
depending on indoor unit types, until the number
of recovery control reaches the predetermined
number.

NOTE
The PMV, indoor fan, or louvers may operate through
the outdoor unit instruction.
For its detail, refer to the outdoor unit service guide.

Remarks

Indoor unit during cooling
thermostat OFF or FAN
operation stops the indoor fan
and displays "Operation
standby ".

Control is performed per one
hour or when the outdoor unit
determines its need.(It varies
depending on the indoor units
connected.)

• A model with a drain pump :

4-way

Concealed Duct

High Static Duct

Fresh air

Compensation
control for short
intermittent
operation

Drain pump
control

Elimination of
retained heat

HA control

1) For 3 minutes after start of operation, the opera-

tion is forcedly continued even if the unit enters in
Thermostat-OFF condition.

2) However the thermostat is OFF giving prior to

COOL/HEAT selection, READY

for operation

and protective control.

1) In cooling operation (including DRY operation),

this control anytime operates the drain pump.

2) During operation of the drain pump, if the float

switch operates, the drain pump continuously
operates and a check code is issued.

3) During stop status of the drain pump, if the float

switch operates, the thermostat is forcedly off and
this control operates the drain pump. After
continuous operation of the float switch for approx.
5 minutes, this control stops the operation and a
check code is issued.

1) When the unit stopped from [HEAT] operation, the

indoor fan operates with [L] for approx. 30 seconds.

1) ON/OFF operation is available by input of HA

signal from the remote site when connected to
remote controller or the remote ON/OFF interface.

2) HA control outputs ON/OFF status to HA terminal.

3) The input-output specifications of HA conform to

JEMA standard.

Usually the priority is given to
5 minutes at outdoor controller
side.

Check Code [P10]

When using HA terminal
(CN61) for the remote ON/
OFF, a connector sold sepa-
rately is necessary.

In case of group operation, use
the connector to connect HA
terminal to either master or
follower indoor unit.

Refrigerant (Oil)
recovery control in
cooling operation

Indoor units during stop/thermostat OFF or FAN
operation perform following controls when a refrigerant
(compressor oil) recovery signal is received from
outdoor unit at the cooling operation,

(1) Opening the indoor unit PMV at constant valve

opening. (For a maximum of about 4 minutes)

(2) Operating the drain pump for about one minute,

during recovery control and after the control
finished.
Also, indoor unit fan or louvers may operate
depending on the indoor unit type.

Control is performed per two
hours or when the outdoor unit
determines its need.(It varies
depending on the indoor units
connected.)

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