45
7. MODULATION INCORRECT.
IN
OUT
DHW modulates
correctly?
CH modulates
correctly?
Adjust the gas valve to
the correct pressures
(4.0mbar Minimum)
(35.0mbar Maximum)
Are the gas
valve pressures
OK?
Is the boiler
vented of air
and the
heating
pressure set
to 1.6bar?
Refill and
vent the
CH system
to 1.6bar
Remake the wiring
connections from the
front panel PCB or
replace the front panel
control PCB
Check the wiring
& the values of
the front panel
PCB.
Variable
resistance OK?
Is the
pump
running?
230v ac
supply to
pump J9
Blue/brown
Replace the DHW
thermistor
Are the values of the
DHW thermistor OK?
Replace
the main
PCB
Replace
pump head
Is the pump speed set
at max speed (3)?
Set Pump
to number
3 speed.
Clean/descale
or replace the
DHW plate
heat
exchanger
Measure the
CH temp, is it
higher than
85°C and the
DHW temp
lower than the
selected temp.
Check the wiring
and the values of
the front panel
control PCB,
CH variable
resistance OK?
Remake the
connections
or replace
the front
panel PCB
Replace the
main PCB
Are the values of the CH thermistor
OK? Ensure the thermistor is
located to the correct position.
Replace the
CH thermistor.
Yes
Yes
No
No
No
No
No
Yes
No
No
Yes
Yes
No
No
Yes
No
Yes
Yes
No
Yes
No
No
Yes
Yes
No
Summary of Contents for FEB-24E UK
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Page 11: ...11 2 Electrical Components Electrical Circuit Diagram ...
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Page 26: ...26 Central Heating Logic Programme Figure 1 Figure 2 ...
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