5
Operating and fault displays
LED Off
No. Diagnosis
Remedy
5, 6,
Operation: no heat
7, 8
demand to the boiler;
boiler operational.
Operation: no boiler
connected.
Configuration/
Check the
Fault: no
corresponding
communication
connecting lead/
between
cable.
MCM10 module and
Remove boiler fault.
this boiler, although it
is installed.
Replace
MCM10 module.
Tab. 10 Operating and fault displays
1) Another boiler will be enabled automatically in case of heat demand
5.4
Operating and fault indications via the RC35
The operating and fault indications relating to all boilers
and the MCM10 module can be checked on the controller
with EMS BUS control. For an explanation of the displays
on the MCM10 module, see tab. 11. The meaning of all
other displays is given in the documentation of the
controller and boilers.
Display
Description
5H
Break in BUS communication.
4U
Short circuit (4U) or contact break
4Y
(4Y).
EF
Internal electronics fault.
8Y
The external switching contact has
opened.
AE
Jumper configuration fault.
AU
The calculated boiler water
temperature is not reached in time.
AY
A fault has occurred on one or
several boilers.
Tab. 11 Operating and fault indications via the RC35
70
On
Diagnosis
–
Operation: heat
demand to the boiler;
boiler in operation.
–
Remedy
•
Display in case of less than 4 installed boilers.
•
Check the cable between the boiler and the MCM10 module for a possible break.
•
Check the cable for firm seating and contact.
•
Check whether this fault originates in a boiler (
•
Replace MCM10 module.
•
Check flow temperature sensor and its lead.
•
Replace MCM10 module.
•
If a fault is indicated by one of the boilers: replace burner control unit of the corresponding
boiler.
•
If the fault is not indicated by one of the boilers: replace MCM10 module.
•
Check the cable of the external switching contact for a possible break.
•
Check whether the connecting plug is present.
•
Replace MCM10 module.
•
Check whether the jumper has been correctly set.
•
Check whether a sufficient number of boilers functions normally.
•
Remedy the fault on the boiler concerned.
Flashing
Remedy
Diagnosis
–
Configuration:
communication
between this boiler
and MCM10 module.
Fault: boiler fault.
Fault: no
communication
between
MCM10 module and
boiler because it has
been deliberately
removed.
Fault: communication
error between
MCM10 module and
boiler.
boiler installation instructions).
Remedy
Wait until the
configuration has
completed.
1)
Remove fault on the
boiler.
Carry out
configuration reset
(
chapter 4.3).
Check the
corresponding
connecting lead/
1)
cable.
Replace
MCM10 module.
MCM10