Technical data
Servicing
74 POTTERTON COMMERCIAL
120-393 632.4 04.08 Fh
10.12 Operation phases of control and regulation centre LMU
(Press information button)
140
Impermissible LPB segment number
or equipment number
Check setting of regulation
148
Incompatibility between LPB inter-
face/basic unit
Check setting of regulation
151 Internal fault of LMU
Check parameters (see setting table heating specialist or
call-up values),unlock LMU, replace LMU, heating specialist
1)
3)
152 Fault of LMU-parameter setting Repeat programming
153 Boiler locked (reset pressed) Operate unlocking button
1)
154
Plausibility criterion of electronic
STB infringed
Return temperature higher than flow temperature or to fast
temperature increase in the boiler
3)
160 Speed threshold not reached
Fan possible defective, speed threshold set wrongly, no vol-
tage at the output transformer (program number 5920)
3)
161 Max. speed exceeded Check parameters
183 Boiler in parameter setting mode
3)
1)
Stopping, start prevention, re-start after fault removal
2)
Check parameter according to table Setting Table Heating Specialist and program basic settings or call-up internal LMU SW-
diagnosis code and correct respective parameter fault according to fault information!
3)
Switching off and interlock can only be unlocked by reset
4)
Only fault display, no switching off
Display Operating Status Description of function
0 Standby (no heat demands) Burner on stand-by
1 Start prevention
No internal or external release exists (e.g. no water
pressure, lack of gas)
2 Fan startup Self-test for burner start and fan startup
3 Pre-purging time
Pre-purging, fan deceleration time to starting load
speed
4 Waiting time Internal safety tests
5 Ignition phase
Ignition and start of safety period flame forming
Ionisation current build-up
6 Safety time constant Flame monitoring with ignition
7 Safety time variable Flame monitoring without ignition
10 Heating mode Room heating mode, burner in operation
11 Hot water mode HW-tank charging, burner in operation
12
Parallel operation for heating and hot
water
Heating and hot water mode
Fault
code
Fault description Explanations/causes