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Building Technologies Division CC1N7491en

18.07.2018

Error code list

QAA73

display of

error code

Meaning of QAA73 text display

Internal

diagno

stics

code

Cause

Error 10 Error outside sensor 1 Short-circuit of outside temperature sensor

Error 20 Error boiler temperature sensor 1 1 Short-circuit of boiler temperature sensor

Error 20 Error boiler temperature sensor 1 2 Open-circuit of boiler temperature sensor

Error 28 Error flue gas temperature sensor 1 Short-circuit of NTC flue gas sensor

Error 28 Error flue gas temperature sensor 2 Open-circuit of NTC flue gas sensor

Error 50

Error DHW temperature sensor / thermostat

1 Short-circuit of DHW sensor

Error 50

Error DHW temperature sensor / thermostat

2 Open-circuit of DHW sensor

Error 61 Error room unit 1 20 No telegram received within the timeout time

Error 110 Safety limit thermostat lockout 0 Opening of high limit thermostat

Error 119 Water pressure switch has cutout 0 --

Error 125 Maximum boiler temperature exceeded 20 Pump error due to no temperature gradient

Error 125 Maximum boiler temperature exceeded 21 Pump error due to high temperature check

Error 130 Maximum flue gas temperature exceeded 0 --

Error 131 Burner lockout 0

Pump error due to temperature check or

NTC flue gas sensor

Error 133

Safety time for flame establishment

exceeded

0 --

Error 151 BMU internal error 32 Not existing Zeiko number

Error 151 BMU internal error 33-41 Time overrun in time slot detected

Error 151 BMU internal error 48 Not existing cycle number

Error 151 BMU internal error 65

Program counter was in undefined ROM

area

Error 151 BMU internal error 66 Not allowed interrupt vector

Error 151 BMU internal error 67 Stack overflow

Error 151 BMU internal error 68 Error in calculating the heating demand

Error 151 BMU internal error 82 Invalid init state

Error 152 Error parameter setting 20 Invalid parameter version number

Error 152 Error parameter setting 21 Invalid software type

Error 152 Error parameter setting 22 Invalid CRC parameter

Error 155 Remote lockout release blocked -- Not displayed on the LMU34, but on QAA73

Error 156 Error supply voltage 20

Low Voltage Fault (burner control start

prevention)

Error 156 Error supply voltage 21

Low Voltage Fault (indication, no start

prevention)

Error 156 Error supply voltage 22

Over Voltage Fault (indication, no start

prevention)

Error 158 Error condensate 0 Condensate pump continuous operation