Saunier Duval THEMA F 23 E Installation Instruction
22
• Remove clip holding pipe to heat exchanger in
rear of water valve. From front of boiler, grip clip
with long nosed pliers and pull upwards.
• Unscrew and remove large screw holding water
valve to back plate of reversing valve assembly,
see diagram 32.
• Disengage water valve from reversing valve and
remove from boiler.
Note: When disengaging water valve from heat
exchanger pipe, check that non-return valve is not
held on end of pipe. If so, carefully separate pipe
from valve to ensure that small spring and plunger
do not fly out and are lost.
• To replace diaphragm, undo five screws and
separate main components of water valve.
• If white diaphragm cover is to be replaced, sepa-
rate original from water valve end casting and fit
replacement cover.
• Fit replacement diaphragm , making sure that
metal disc FACES diaphragm cover and beaded
edge of diaphragm is correctly fitted in correspond-
ing groove in both cover and plastic housing, see
diagram 35.
• Reassemble water valve, evenly tightening five
screws.
• Fit water valve actuating pin into hole in dia-
phragm cover, through nose end of valve and and
push in until flush, or slightly below, nose end of
valve.
Note: Apply silicone grease to pin before fitting.
• Refit water valve to boiler, locating nose end into
rear of reversing valve assembly, 'springing' heat
exchanger pipe to gain clearance as necessary.
Fit large water valve retaining screw but do not
tighten fully at this stage.
• Apply silicone grease to 'O' ring and fit onto end
of heat exchanger pipe. Fit pipe into water valve
by pulling it forward. Make sure that 'O' ring is cor-
rectly located.
• Whilst holding pipe in rear of water valve, fit re-
taining clip. This should easily clip over pipe and
should NOT have to be forced. If resistance is ex-
perienced, either pipe is not correctly fitted in rear
of water valve or clip is not being fitted properly
through slot between back plate and plastic hous-
ing of water valve. When clip is fitted, check con-
nection by pushing pipe back away from water
valve.
• Refit telescopic connecting pipe to inlet of wa-
ter valve after applying silicone grease to 'O' ring.
Fit retaining clip into groove on connecting pipe,
through slot between back plate and water valve
plastic housing. Check connection by pulling pipe.
Make sure that clip is not loose and likely to fall out
at a later date. If in doubt, fit a new clip.
• With both flow regulator and and plastic filter
washer in place, refit connecting nut to inlet con-
nection and tighten.
• Open isolating valve on cold water inlet connec-
tion and check for leaks.
• Replace microswitch assembly.
rear of water valve. From front of boiler, grip clip
with long nosed pliers and pull upwards.
• Unscrew and remove large screw holding water
valve to back plate of reversing valve assembly,
see diagram 32.
• Disengage water valve from reversing valve and
remove from boiler.
Note: When disengaging water valve from heat
exchanger pipe, check that non-return valve is not
held on end of pipe. If so, carefully separate pipe
from valve to ensure that small spring and plunger
do not fly out and are lost.
• To replace diaphragm, undo five screws and
separate main components of water valve.
• If white diaphragm cover is to be replaced, sepa-
rate original from water valve end casting and fit
replacement cover.
• Fit replacement diaphragm , making sure that
metal disc FACES diaphragm cover and beaded
edge of diaphragm is correctly fitted in correspond-
ing groove in both cover and plastic housing, see
diagram 35.
• Reassemble water valve, evenly tightening five
screws.
• Fit water valve actuating pin into hole in dia-
phragm cover, through nose end of valve and and
push in until flush, or slightly below, nose end of
valve.
Note: Apply silicone grease to pin before fitting.
• Refit water valve to boiler, locating nose end into
rear of reversing valve assembly, 'springing' heat
exchanger pipe to gain clearance as necessary.
Fit large water valve retaining screw but do not
tighten fully at this stage.
• Apply silicone grease to 'O' ring and fit onto end
of heat exchanger pipe. Fit pipe into water valve
by pulling it forward. Make sure that 'O' ring is cor-
rectly located.
• Whilst holding pipe in rear of water valve, fit re-
taining clip. This should easily clip over pipe and
should NOT have to be forced. If resistance is ex-
perienced, either pipe is not correctly fitted in rear
of water valve or clip is not being fitted properly
through slot between back plate and plastic hous-
ing of water valve. When clip is fitted, check con-
nection by pushing pipe back away from water
valve.
• Refit telescopic connecting pipe to inlet of wa-
ter valve after applying silicone grease to 'O' ring.
Fit retaining clip into groove on connecting pipe,
through slot between back plate and water valve
plastic housing. Check connection by pulling pipe.
Make sure that clip is not loose and likely to fall out
at a later date. If in doubt, fit a new clip.
• With both flow regulator and and plastic filter
washer in place, refit connecting nut to inlet con-
nection and tighten.
• Open isolating valve on cold water inlet connec-
tion and check for leaks.
• Replace microswitch assembly.
To replace gas valve
• Ensure gas supply is off.
• Disconnect two black electrical leads from gas
valve modulating coil.
• Ensure gas supply is off.
• Disconnect two black electrical leads from gas
valve modulating coil.
REPLACEMENT OF PARTS
Des 058
• Disconnect two white and one red lead from gas
valve main solenoid.
• Pull off clear plastic tube from gas valve to sealed
chamber tapping point.
• Unscrew main gas supply pipe nut on top of gas
valve, releasing spark ignition unit bracket, see dia-
gram 36.
• From below boiler, unscrew gas valve connec-
tion between gas valve and fixing jig isolating cock.
• Unscrew and remove two screws securing gas
valve to bottom plate of boiler.
• Remove gas valve from boiler.
• Refit replacement gas valve in reverse order to
removal.
Note: Use new 'O' ring provided between gas valve
and burner supply pipe.
• Refit electrical connections to replacement gas
valve as follows:
valve main solenoid.
• Pull off clear plastic tube from gas valve to sealed
chamber tapping point.
• Unscrew main gas supply pipe nut on top of gas
valve, releasing spark ignition unit bracket, see dia-
gram 36.
• From below boiler, unscrew gas valve connec-
tion between gas valve and fixing jig isolating cock.
• Unscrew and remove two screws securing gas
valve to bottom plate of boiler.
• Remove gas valve from boiler.
• Refit replacement gas valve in reverse order to
removal.
Note: Use new 'O' ring provided between gas valve
and burner supply pipe.
• Refit electrical connections to replacement gas
valve as follows:
- BLACK leads to modulating coil.
- WHITE leads to EV1 and EV2 terminals of main
- WHITE leads to EV1 and EV2 terminals of main
solenoid
- RED lead to COM terminal of main solenoid.
To replace modulating coil
• Ensure gas supply is off.
• Disconnect two black electrical leads from gas
valve modulating coil.
• Unscrew and remove two screws holding modu-
lating coil to gas valve and remove coil from gas
valve.
• Fit replacement modulating coil in recerse order
to removal.
• Reconnect electrical leads to replacement coil.
Note: All boilers are tested and factory set during
manufacture. Should it be necessary to reset a gas
valve, for example after replacement, refer to 'Set-
tings'.
• Ensure gas supply is off.
• Disconnect two black electrical leads from gas
valve modulating coil.
• Unscrew and remove two screws holding modu-
lating coil to gas valve and remove coil from gas
valve.
• Fit replacement modulating coil in recerse order
to removal.
• Reconnect electrical leads to replacement coil.
Note: All boilers are tested and factory set during
manufacture. Should it be necessary to reset a gas
valve, for example after replacement, refer to 'Set-
tings'.
Diagram 35
Diagram 36
Mec 117