Toshiba HWS-1402H-E Diagnosis flow chart for each error code, Hydro unit failure detection

9-4. Diagnosis flow chart for each error code

9-4-1. Hydro unit failure detection

[A01] Error Pump flow determination

Perform air vent

Yes

[A01] occurs

Operation restarts

Pump rotates	No (No pump sound)
Yes	Flow switch is	No
	connected to board
Excess air noise	Yes
comes from inside
the pump

Connect flow switch connector to board

No	Built-in pump is	No
	connected to board
	Yes

Connect pump connector to board

	Flow switch is normal		No	Replace flow switch
Chattering noise comes	No
from flow switch		Yes
No				Replace pump
Pump stops 2-3	Yes
minutes after its rotation
started

No

Flow shortage

(Identify causes, and resolve)

TC sensor characteristic	No
is correct
Yes

	Replace TC sensor
Dirt clogging inside
	Remove waste
water circuit
(strainer)
12 M or longer water	Fit buffer tank and the
pipe to a branch,
	second pump
or 5 or less branches

Flow switch is normal

Yes

No

Attach or replace

flow switch

Water heat exchanger control board is defective, replace it

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