FAULT FINDING
54
Mini
--- Installation & Servicing
Continued from
page 49
Adjust the max setting
on the gas valve. Refer
to frame 29. Check that
max burner pressure*
can be achieved.
Is the cold water supply
adequate? refer to frame
6 and Table 1 at page 4.
yes
no
no
no
no
no
no
no
no
yes
yes
yes
yes
yes
yes
Is there between 0V dc and
16V dc at the connections
on the modulating coil?
(0=min, 16=max)
Is there a temperature rise
of 35
˚
C across the DHW
circuit at:
10.0 L/min 24 kW model
11.6 L/min 28 kW model
13.1 L/min 32 kW model
Rectify gas supply
fault.
Is there > 17 mbar
gas pressure at the
gas inlet?
Is there max burner
pressure* when the
boiler first lights?
Is the maximum water
flow correct
10.0 L/min 24 kW model
12.0 L/min 28 kW model
14.0 L/min 32 kW model
Rectify water supply
fault.
Check the DHW inlet
filter. Remove debris
and clean or replace
filter.
With the DHW hot
does the burner
pressure modulate if
the DHW temperature
setting is reduced to
minimum?
Boiler Operating
Correctly
Replace faulty gas
valve.
Is the continuity of the
modulator harness O.K?
Repair or replace
faulty wiring.
Replace faulty PCB
* see Table 2 at page 4 for the correct value
yes
Is the burner pressure within
min and max value* with
the boiler running?
no
Adjust burner pressure.
Refer to frame 29.
yes
FA
UL
T
F
IND
ING
