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Subject to technical amendments without prior notice | 83055400iUK – 2.1 | ait-deutschland GmbH
No.
Display
Description
Remedy
724
Tempdiff defrosting
Please call fitter
Temperature spread in the heating circle is > 15 K during
defrosting (=danger of frost).
Check function and location of the flow and
return sensor, HCP capacity, overflows and
heating circles.
725
System error DHW
Please call fitter
Domestic hot water faulty, desired tank temperature is fallen
below substantially.
Check circulating pump DHW, tank filling,
shutoff move and 3-way valve. Ventilate hot
water and SW.
726
Sensor mixing circ 1
Please call fitter
Break or short-circuit in the mixing circle sensor.
Check mixing circle sensor, plug and
connection line.
727
Brine pressure
Please call fitter
Brine pressure pressostat has responded during the pre-rinsing
time or during operation.
Check brine pressure and brine pressure
pressostat.
728
Sensor HS Off
Please call fitter
Break or short-circuit in the heat source sensor at the HS outlet. Check heat source sensor, plug and
connection line.
729
Rotating field error
Please call fitter
Compressor without power after switching on.
Check rotating field and compressor.
730
Screed heating error
Please call fitter
The screed heating program could not reach an FL temperature
level in the specified time interval. Screed heating program
continues running.
The screed heating program could not
reach an FL temperature level in the
specified time interval. Screed heating
program continues running.
731
Timeout TDI
The temperature required for thermal disinfection could not be
reached within the set switching times.
732
Cooling fault
Please call fitter
The hot water temperature of 16 °C has been fallen short of
several times.
Check mixer and heating circulation pump.
733
Anode fault
Please call fitter
Fault input of the impressed current anode has responded.
Check connection line between anode and
potentio stat. Fill SW tank.
734
Anode fault
Please call fitter
Error 733 present for more than two weeks and domestic hot
water is locked.
Acknowledge error in order to release
domestic hot water preparation again.
Rectify 733.
735
Error Ext. En
Please call fitter
Only possible with installed expansion board: Break or short-
circuit in the sensor “External energy source”.
Check sensor “External energy source”, plug
and connection line.
736
Error solar collector
Please call fitter
Only possible with installed expansion board: Break or short-
circuit in the “solar collector” sensor.
Check “solar tank” sensor, plug and
connection line.
737
Error solar tank
Please call fitter
Only possible with installed expansion board: Break or short-
circuit in the “solar tank” sensor.
Check “solar tank” sensor, plug and
connection line.
738
Error mixing circle 2
Please call fitter
Only possible with installed expansion board: Break or short-
circuit in the “mixing circle 2” sensor.
Check “mixing circle 2” sensor, plug and
connection line.
739
Error mixing circle 3
Please call fitter
Only possible with installed expansion board: Break or short-
circuit in the “mixing circle 3” sensor.
Check “mixing circle 3” sensor, plug and
connection line.
750
Return sensor external
Please call fitter
Break or short-circuit in the external return sensor.
Check external return sensor, plug and
connection line.
751
Phase monitoring fault
Phase-sequence relay has responded.
Check rotary field and phase-sequence
relay.
752
Flow error
Phase-sequence relay or flow switch has responded.
see errors No. 751 and No. 717.
755
Lost connection to slave
Please call fitter
A slave has not responded for more than 5 minutes.
Check network connection, switch, and IP
addresses. Perform HP search if necessary.
756
Lost connection to master
Please call fitter
A master has not responded for more than 5 minutes.
Check network connection, switch, and IP
addresses. Perform HP search if necessary.
757
Low-pressure fault in W/W-
appliance
Low-pressure pressostat in the W/W-appliance has triggered
either repeatedly or for more than 20 seconds.
If this malfunction occurs three times, the
installation can only be cleared again by
authorised service personnel!
758
Defrosting malfunction
Five times in a row, defrosting has either lasted longer than 10
minutes or was terminated with a feed temperature of < 10 °C.
Check flow rate.
Check flow sensor.
759
TDI message
Unable to correctly carry out thermal disinfection 5 times in
succession.
Check setting of additional heat generator
and safety temperature limiter.
760
Defrosting fault
Defrosting ended 5 times in succession by maximum time
(strong wind impinges on evaporator) .
Protect the fan and evaporator from strong
wind.
761
LIN timeout
LIN connection interrupted
Check cable/contact.
