Troubleshooting
3
Subject to modifications resulting from technical improvements!
Buderus Ltd. • http://www.buderus-domestic.co.uk
Servicing manual for wall-mounted condensing gas boiler 600 Series 11S/19S/24S/24C • Issued 02/2006
31
Fig. 28
Fault warning message 7A: Voltage in UBA too low or too high
Flashing
Voltage in UBA too low/high
Contact local energy-supply
utility
Yes, on fourth attempt to start up
Remove the casing (page 48)
A
No
No
No
Yes
Yes
A
"reset"
New fault warning
message
7A
?
Check Mains voltage
(195 V to 253 V)
Mains voltage
OK?
600 Series
11S / 19S / 24S / 24C
OK
Connect correctly
Yes,
on second and
third attempts
to start up
7
Is regulator connected to
incorrect terminals?