Toshiba HWT-602S21SM3W-E(TR) Service Manual page 150

Outdoor LED
Check code
indication
[P19]
(No specific description indicates outdoor unit parts.)
[4-way valve reversal trouble]
Does 4-way valve
work correctly?
NO
(Check pipe temp. etc.
in cooling/heating
operation)
YES
Temperature
NO
sensor normal?
TE sensor
TS sensor
YES
Is the flow of the
NO
refrigerant by the
PMV normal?
YES
NO
Indoor TC, TCJ
sensor normal?
YES
[4-way valve relay operation check]
Service switches SW01 and SW02 can be used to check the operation of the
4-way valve relay.
Use to check whether there are any problems with the 4-way valve or 4-way
valve coil.
[Method of operation]
1) Confirm D800 to D804 are off (or rapidly flashing) and that D805 is
lit up. If D800 to D804 are slowly flashing or D805 is flashing then push
and hold down SW01 and SW02 at the same time for at least 5 seconds.
D800 to D804 will turn off (or rapidly flash) and D805 turn on.
2) Push and hold down SW01 for at least 5 seconds. D804 will start slowly flashing.
3) Push SW01 until reaching the below [Self-preservation valve operation].
Self-preservation valve suck operation
(Heating)
Self-preservation valve secession operation
(Cooling)
: Off : Light
4) Push SW02 until D805 starts rapidly flashing.
5) Push and hold down SW02 for at least 5 seconds. D804 will start slowly
flashing, D805 will turn on, and the 4-way valve will be operated.
6) Push and hold down SW01 and SW02 at the same time for at least 5 seconds
or wait 2 minutes to return to normal control.
149
Check and Action procedure
Is the coil
resistance
value of 4-way
valve normal?
The voltage
Replace
variation due to
TE, TS sensor
the confirmation
of 4-way valve
relay operation,
refer to below?
Check PMV
and replace
Check outdoor
control board
If defective,
replace it
Replace
TC, TCJ sensor
Check indoor PC board
Failure → Replace
D800
D800
: Flash (5 times/sec)
NO
Replace
4-way valve coil
YES
NO
Check 4-way valve
If defective, replace it
YES
PC board
<401, 601> MCC-1768
<801, 1101> MCC-1675
<801, 1101, 1401>MCC-1781
NO
(3 phase)
D801 D802 D803 D804
D801 D802 D803 D804