Toshiba MMU-AP0091H service manual 172, May become, Detection Flow Almost normal Cooled

172

Phenomenon which appears as result

Correspon

(Corresponding indoor unit or flow selector unit)

Example of

Part name

Trouble mode

Operation mode

l Abnormal

Judgment and position to be checked

ding indoor

May become

refrigerant

unit

Not

Not

cooling sound

Detection of

flow

almost normal

cooled

heated

¡ Circulating

check code

capacity

sound

Single cooling

l Indoor unit,

Simultaneous cooling (Indoor cooling)

¡

•

Operation is changed from heating to cooling.

Selector unit

Simultaneous heating (Indoor cooling)

Clogging

Single heating

l Indoor unit,

SVSS valve

Simultaneous cooling (Indoor heating)

¡

•

Refrigerant impact sound is heard at defrost time.

Selector unit

Simultaneous heating (Indoor heating)

Single heating

• Refrigerant sound may be heard from SVSS valve

circuit.

Leakage

Simultaneous cooling (Indoor heating)

¡

¡ SVSS circuit

•

Temperature of suction gas pipe at outdoor side of the

Simultaneous heating (Indoor heating)

selector unit is higher than that of normal selector unit.

Single cooling (SV11 ON)

Simultaneous cooling (Indoor cooling)

¡

P15

• Gas short is observed and PD and PS may be lower

Check valve

Simultaneous heating (Indoor cooling)

Discharge–Liquid

[Gas leak

than those in normal time.

Capillary clogging

Single heating

detection]

• TD and TS may be higher than those in normal time.

bypass capillary,

Simultaneous cooling (Indoor heating)

¡

Check valve

Simultaneous heating (Indoor heating)

Check valve

Single cooling (SV11 OFF)

¡

¡ Check valve

• Refrigerant sound may be heard from check valve.

leakage

circuit

•

Discharge gas pipe is cold or it may be frozen.

Piping

Incorrect piping

Single cooling

• TCJ and TC1 are heated same as heating.

Discharge pipe

¡

(Heating circuit)

Discharge pipe ↔

Simultaneous cooling (Indoor cooling)

Liquid pipe

•

Discharge gas pipe at outdoor side of selector unit is

Suction gas pipe

Simultaneous heating (Indoor cooling)

Gas pipe

fairly heated.

Signal line

Disconnection

Contact error

In some cases, phenomena such as above occur.

Power supply line

Miswiring