Buderus Logano plus GB312 Installation And Service Instructions Manual page 58

10
Troubleshooting
1)
Type Display code Fault code
V 8Y 591
V 9Y 500
501
502
503
V CY 566
V CY 567
Table 23 Fault displays
1) V = interlocking; B = inhibiting; BC = operating code
58
Cause Description
Faults when checking the SAFe pressure switch
safety sequence. has not tripped.
Internal SAFe relay fault. Internal electronic fault
on SAFe.
Return temperature The control unit receives
unrealistic values from
< 23 °F (< -5 °C) (circuit
the return sensor.
break)
Return temperature The controller receives
unrealistic values from
> 266 °F (> 130 °C) (short-
the return temperature
circuit)
sensor.
Testing sequence/ Measure
Cause
Check whether the gas Ensure a gas supply
supply pressure is pressure of > 3 inches
> 3 inches W.C. W.C.
Check setting of SAFe
pressure switch. Adjust setting of SAFe
pressure switch to 3
inches w.c.
Check connector on gas
valve is properly seated. Insert connector
properly.
Replace SAFe pressure
switch and wiring.
Replace SAFe.
Press Reset button and If fault recurs after
wait to see if fault is Reset, SAFe must be
eliminated. replaced.
Check the connecting Replace connecting
cable between the SAFe cable if necessary.
and the return
Rectify contact problem
temperature sensor.
if necessary.
Check electrical
Replace temperature
connection of connecting
sensor is necessary.
cable to SAFe.
If temperature sensor
Check resistance levels of
resistances are correct
temperature sensor
but voltages incorrect,
against table.
replace SAFe.
Check voltage at
temperature sensor
terminals on SAFe against
table.
Check the connecting Replace connecting
cable between the SAFe cable if necessary.
and the return
Rectify contact problem
temperature sensor.
if necessary.
Check electrical
Replace temperature
connection of connecting
sensor is necessary.
cable to SAFe.
If temperature sensor
Check resistance levels of
resistances are correct
temperature sensor
but voltages incorrect,
against table.
replace SAFe.
Check voltage at
temperature sensor
terminals on SAFe against
table.
Logano plus GB312 – 6 720 806 273 (2013/01)