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52
FA ROTEX HPSU monobloc compact • 09/2017
8
x
Errors, malfunctions and messages
8.3
Error codes
In the case of all malfunctions / error messages due to possible defective sensors, always check all accompanying connec-
tion cables, connecting points (plug contacts seated correctly) and printed circuit boards before exchanging them.
Component assignment: see fig. 3-1 to fig. 3-3 and fig. 8-4
Code
Malfunction /
error message
Component/
Designation
Causes and possible fault elimination
Display Internal
E75
—
Fault feed flow
sensor
Feed temperature sen-
sor t
V, BH
Feed temperature sensor defective.
Ɣ
Check, replace.
E76
—
Storage tank tem-
perature sensor
fault
Storage tank tempera-
ture sensor t
DHW
Storage tank temperature sensor t
DHW
or connecting cable defec-
tive or not connected.
Ɣ
Check, replace.
Ɣ
Check [Storage Config] setting.
E81
—
Communication
fault
Circuit
boardRoCon BM2C
Parameter storage in the EEPROM disturbed.
Ɣ
Contact a ROTEX service technician.
E88
—
Circuit
boardRoCon BM2C
Parameter storage in the external flash memory disturbed.
Ɣ
Contact a ROTEX service technician.
E91
—
Connected CAN mod-
ules
CAN module bus ID duplicated, set unique data bus address.
E128
—
Fault T-return
Return flow temperature
sensor t
R
(outdoor unit)
Return flow temperature sensor t
R
connecting cable defective.
Ɣ
Check, replace.
E129
—
Fault pressure
sensor
Pressure sensor DS
Pressure sensor DS defective.
Ɣ
Check, replace.
E198
—
Flow measure-
ment not plausible
Flow sensor FLS (out-
door unit),
3-way switch
valve3UVB1
Error occurs when 3-way switch valve 3UVB1 is in bypass position,
the internal circulation pump is running but a volumetric flow that is
too low is measured.
Required minimum water flow rate:
–
"Heating", "Cooling" operating mode: 420 l/h
–
Automatic thawing function (
) active: 780 l/h
–
BUxx support: 780 l/h
–
Air in heating system.
Ɣ
Vent.
–
Internal circulation pump is not running.
Ɣ
Check electrical connection and controller settings. If circu-
lation pump is defective, replace it.
–
Flow sensor FLS dirty, clogged.
Ɣ
Check, clean.
–
Flow sensor FLS defective.
–
3-way switch valve 3UVB1 valve drive defective.
Ɣ
Check, replace.
E200
—
Communication
fault
Electrical components
Communication between RoCon BM2C and printed circuit board
A1P is disturbed.
–
Outdoor unit is not connected
–
Wiring or connections, poor contact.
Ɣ
Check, replace
E8005
—
Water pressure in
heating system too
low
Pressure sensor DS
Water pressure has fallen below permissible minimum value.
–
Insufficient water in the heating system.
Ɣ
Check heating system for leaks, top up water.
–
Pressure sensor DS defective.
Ɣ
Check, replace.
E8100
—
Communication
Electrical components
Initialisation after heat pump start failed.
Printed circuit board A1P (outdoor unit) defective.
Ɣ
Check, replace.
E9000
—
Temporary internal
message
—
Not relevant for proper system operation.