Water flow switch activates
plug 33.
Check water flow switch. Replace
if necessary.
no
no
no
Display message
Fault F5/F9
after approx. 51 seconds
Check cabling and plug-in connectors of the
blower , as well as blower itself. Check
proper power supply to the blower.
yes
yes
Fault F5/F9
after approx. 51 seconds
no
Check flue gas system and differential air
pressure switch.
Differential air pressure switch enables
start-up.(Close contacts between terminals
X8.7 and X8.8)
104VRAC (DC)
(symbol
A
appears).
unit and it’s plug-in connections.
Check condensate line and flue gas
system for leaks.
Fault F4
Fault F4
Fault F4
check gas supply pressure.
between brown and blue must be present
during start-up, plug 35
6
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5581 775 1.3
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