Download SERVICE MANUAL - Cool Designs Ltd

+00A09-002_01EN_SVM_ALL_Air_to_Water.book Page 75 Monday, October 5, 2009 2:09 PM
[A02] Error Temperature rise and error short circuit
Start
(TWI,TWO,THO 70°C)
TWI, TWO, and THO
sensor characteristics are
correct
No
Replace TWI, TWO,
and THO sensors
Yes
Flow switch is normal
No
Replace flow switch
Yes
Water outlet
temperature is 70°C
or higher
No
Yes
Hot water from
boiler or other circuits does
not come in
Yes
Correct water circuit
(To prevent hot water of
other circuits from entering)
Yes
Failure of backup heater
(Too large heater input,
thermostat short circuit)
No
Backup heater is energized
(Measure heater current)
No
Replace water heat exchange control board
Replace heater unit
75
Toshiba