F37
''LOW WATER
PRESSURE
FAULT
''
It occurs when water
pressure sensor
is below than
(0.4 bar).
Check whether water pressure
value is
>
0,4 bar for central heating
circuit from LCD.
Replace the
main
board.
Fill the system with
water until pressure reaches to
1.5-2 bars (
boiler
will be recovered from failure
at pressures over 0.8 bars).
Check
isolating
valves and CH system
for any
leakage.
NO
YES
Pressure sensor
cables may
be not
mounted,
or there may be a loose
contact. Check the
cables
NO
YES
Replace the cables in
case of any problem.
Dismount
electrical
connector on water pressure sensor
when the power of the device is still on,
and measure the DC voltage. Check
whether the voltage is in the
range of 4.9-5.1 V DC.
NO
YES
Replace the
main
board.
Replace the pressure
sensor.
NO
YES
Check 3 bar safety valve, replace
it if needed.
NO
Check pressure inside expansion
vessel and repressurize or replace
it if needed.
NO
Check
all water
connections in the
boiler.
NO
There may be a puncture on heat
exchanger coil.Check and replace
heat exchanger if needed.
F34
''LOW SUPPLY
VOLTAG
E
FAULT
''
It occurs when
supply voltage is under
170V. Check whether
the
supply voltage
is
below
170 V.
Replace
main
b
oard.
Unless voltage returns to
normal value, the system
remains blocked and the
heat demand is not
fulfilled.
NO
YES
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