Saunier Duval THEMA F 23 E Installation Instruction

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REPLACEMENT OF PARTS
• Unclip thermistor from pipe.
• Pull off electrical cennections from thermistor.
• Fit replacement thermistor in reverse order to re-
moval.
Note: No heat sink compound is required. The po-
larity of the connections is not important.
To replace overheat thermostat
• Locate the overheat thermostat on the right
hand side of the heat exchanger.
• Pull off the electrical connections from the ther-
mostat.
• Unscrew and remove two screws holding ther-
mostat to heat exchanger.
• Fit replacement thermostat in reverse order to
removal, using heat sink compound on the con-
tact  surface of  thermostat.
• Refit electrical leads, the polarity is not impor-
tant.
To replace combustion chamber insulation
Front section
• Remove combustion chamber from boiler as
described in 'Routine Cleaning and Inspection'.
• Slide side panels out of combustion chamber
sides.
• Lift front insulation panel free from retaining lugs
and away from cover.
• Fit replacement panels in reverse order to re-
moval.
Rear panel
• Remove burner from boiler as described in 'Rou-
tine Cleaning and Inspection'
.
• Remove clip from base of insulation panel.
• Pull bottom edge of insulation panel forward,
downward and out from behind heat exchanger.
• Fit replacement panel in reverse order to re-
moval.
• Replace burner into boiler in reverse order to re-
moval.
To replace ignition electrode
• Remove combustion chamber from boiler as
described in 'Routine Cleaning and Inspection'.
• Pull off ignition leads from ignition electrode.
• Unscrew and remove two screws holding igni-
tion electrode onto burner.
• Fit replacement ignition electrode in reverse or-
der to removal.
• Refit ignition leads, the polarity is not important.
To replace flame sense electrode
• Remove combustion chamber from boiler as
described in 'Routine Cleaning and Inspection'.
• Pull off  lead from flame sense electrode.
• Unscrew and remove screw holding earth lead
to flame sense electrode.
• Unscrew and remove screw holding flame sense
electrode onto burner.
• Fit replacement flame sense electrode in reverse
order to removal.
• Refit lead.
To replace burner
• Pull off ignition and flame sense leads from elec-
trodes.
• Remove burner from boiler as described in 'Rou-
tine Cleaning and Inspection'
.
• Remove ignition and flame sense electrodes as
described in previous sections.
• Unscrew and remove two screws holding burner
injector bar to burner and remove injector bar.
• Asemble replacement burner, supplied in parts,
as follows:
• Fit burner injectors to injector bar and tighten.
• Assemble burner elements (14) into front and rear
burner supports with securing pins and rods, using
original burner for guidance.
• Fit burner injector bar to burner.
• Fit ignition and flame sense electrodes to burner.
• Fit replacement burner to boiler in reverse order
to removal.
• Reconnect ignition and flame sense leads to
electrodes. Reconnect earth lead to flame sense
electrode. The polarity of the ignition leads is not
important.
To replace burner injectors
• Remove burner as described previously.
• Remove ignition and flame sense electrodes as
described in previous sections.
• Unscrew and remove two screws holding burner
injector bar to burner and remove injector bar.
• Unscrew and remove burner injectors from burner
bar.
• Fit replacement injectors to injector bar and
tighten.
Note: make sure that injector size, marked on each
injector, is the same as that given in 'Technical Data'.
• Reassemble burner and replace into boiler in
reverse order to removal.
To replace timeclock
• Gain access to rear of lower control panel as
described in 'Routine Cleaning and Inspection'.
• Unscrew and remove two screws holding
timeclock to lower control panel.
• Remove PCB cover.
• Remove timeclock plug from connection CN7
on main PCB.
• Fit replacement timeclock in reverse order to re-
moval.