Toshiba MMU-AP0151MH サービスマニュアル

1) Applied models

Q

Indoor unit: MMX-APXXX,
Outdoor unit: MMY-MAPXXXHT8, MMY-MAPXXXT7

R

Indoor unit: MMX-APXXX,
Outdoor unit: MMY-MAPXXXFT8

S

Indoor unit: MMX-APXXX,
Outdoor unit: MCY-MAPXXXHT, MCY-MAPXXXHT2D

2) Required tools / measuring devices

• Screwdrivers (Philips, Minus), spanner, radio pinchers, nipper, push pin for reset switch, etc.

• Tester, thermometer, pressure gauge, etc.

3) Confirmation before check (The following items are not troubles.)

When a trouble occurred, advance the check operation in the following procedure.

NOTE) While a check operation is performed, a malfunction of the microprocessor may be caused due to

condition of the power supply or the external noise. If there is any noise source, change wires of the
remote controller and signal wires to shield wires.

Trouble

Check the check display 
on the interface P.C. board 
of the outdoor unit.

Check position or part 
in which trouble occurred.

1

2

3

4

5

6

Compressor does not operate.

Indoor fan does not work.

Outdoor fan does not rotate, or
fan speed changes.

Indoor fan does not stop.

Start/stop operation on remote
controller is unavailable.

——

• Is not delayed for 3 minutes? (3 minutes after compressor-OFF)

• Is not thermostat OFF?

• Is not the fan operating or timer?

• Is not the system initially communicating?

Heating operation cannot be performed under condition of outside tempera-
ture 21°C or higher.

Cooling operation cannot be performed under condition of outside tempera-
ture –5°C or lower.

• Is not the cold draft prevention being controlled in heating operation?

• Is not low cooling operation being controlled?

• Is not a defrost operation being performed?

• Is not after-heat elimination operation being controlled after heating opera-

tion?

• Is not auxiliary unit or remote control being operated?

• Is connecting wire of indoor unit or remote controller correct?