Atmos Multi Mk2, Manual, Page: 11 / 19

2. SUMMARY OF MESSAGES
This section provides a brief description of the warning, blocking and malfunction messages which appear on the
appliances diagnostic display. The causes of these messages are addressed in more detail in section 3.
2.1
Warning messages
A warning message is identified by a letter that appears on the diagnostic display once every 5 seconds, for a period of
1 second, instead of the status message.
Diagnostic display code
Status
message
(Number)
Warning every 5
seconds
Message
b
Incorrect hot water tank temperature reading, value<-10
o
C or> 118
o
C
c Incorrect central heating water pressure, value between 0 and 0.5 bar or 3 and
4 bar (capacity is limited to low setting)
d Incorrect central heating return sensor reading, value<-10
o
C or> 118
o
C
8
h
Incorrect outside sensor reading, value<-15
o
C or>118
o
C
2.2
Blocking messages
A blocking is an error that occurs without causing a malfunction. The appliance waits until the blocking has been
resolved and then continues to operate normally. A blocking is indicated by a permanently lit letter on the diagnostic
display.
Code
Diagnostic
display
Central heating
water display Message
H H Central heating water temperature sensor error value >118
o
C
c
L L Central heating water temperature sensor error, value <-10
o
C
C* Central heating pressure lower than 1 bar (occurs when the plug is inserted
into the power socket)
F Mains frequency error
H Internal error
L Electrical mains plug error-correct supply polarity
n Mains or reference voltage too low
H H
Appliance type recognition error, value >118
o
C
L L Appliance type recognition error, value <-10
o
C
1 0 Appliance type recognition error, control unit is set to 24/80
1 1 Appliance type recognition error, control unit is set to 24/80
plus
2 0 Appliance type recognition error, control unit is set to 32/80
t
2 1 Appliance type recognition error, control unit is set to 32/80
plus
* this code will not be stored in the memory
ATMOS MULTI Mk2 version 2004 Appendix Page 11