Toshiba HWS-802XWHT6-E User Manual
Page 84
83
Toshiba
[A12] Error Heating or Hot water supply heater failure
Water heat
exchanger board DPSW11-1,2
is ON
Replace booster heater
unit and safety valve
Set water heat board
DPSW11-1,2 to ON
A12 abnormality detection
No
(Backup heater NG)
Backup heater or
hot water cylinder terminal
has 230ACV ( ± 23V)
Power is connect
to backup heater or hot water
cylinder terminal
Yes
Yes
Restart
Operation starts under
10 TWI 20°C
Heater backup operation
Heating: Booster heater
Hot water supply: Hot water cylinder heater
After 1 hour since heater operation
started, neither TWI 15°C
nor TTW 20°C is met
Freeze prevention control is detected once
No
No
Place electric wire for
backup heater
Place electric wire for
hot water cylinder
Set breaker for backup
heater to ON
Set breaker for hot water
cylinder to ON
or check indoor wiring
No
Backup heater element
is conductive
Yes
Replace hot water
cylinder heater
No
(Hot water cylinder heater NG)
Hot water
cylinder heater element
is conductive
Yes
Replace TWI or TTW
sensor
No
(See characteristic table in page 101)
TWI, TTW sensor
characteristics are
normal
Yes
Yes
(Refer to hot water
cylinder guide)
Replace water heat
exchange control board
+00A09-002_01EN_SVM_ALL_Air_to_Water.book Page 83 Monday, October 5, 2009 2:09 PM