Strebel S-CB+ Series, Installation Operating & Maintenance Manual

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S-CB
+
Boiler Range Manual
114
Service history
The operational and fault history (total amount and since the last service) of the boiler can be retrieved with the
help of a computer, correct software and an interface cable. This information can be used to specify the mainte-
nance and service proceedings in relation to the boiler (parts).
Water leakage
The water pressure of the heating installation should be more than 1.0 bar and at a maximum of 2.0 bar in normal
operation. When the water pressure drops below the minimum occasionally, there might be a water leak. Check the
boiler and the complete heating installation for any water leakages and have these repaired.
Flue gas & air supply
The flue gas pipes and the air supply pipes must be checked for gas tightness. Also check if the mounting of these
pipes is correct, safe and not damaged. Check the rooftop of the boiler housing for signs of water leakage and
traces of water coming from the air supply pipe, the air vent or any condensate coming from the flue gas pipes.
Gas supply & safeties
The gas pipes must be checked for gas tightness. Also check if the mounting of these pipes is correct, safe and not
damaged. Any built in safeties should be checked for a correct functioning.
Remove complete burner unit
The complete burner unit consists of the fan, the burner plate and the internal burner. To remove this part for an
internal heat exchanger check: remove the six M6 nuts, the ignition cable and the thermal fuse cables. After this,
take out the complete burner unit by moving it forward out of the boiler housing. NOTICE: Watch out not to damage
the burner plate insulation during this operation. While removing the complete burner unplug both of the electrical
and controlling cables of the fan. After all this dismantle the air gas mixing box on the suction side of the fan and
check the blade wheel of the fan.
Burner
Check the burner surface to see if it has damages, signs of rust and/or cracks. When the burner surface is dam-
aged the burner must be replaced. The burner can be cleaned by using a soft (non-metallic) brush. The dust can
be removed with a vacuum cleaner or pressurized air.
Ignition / ionisation electrode
When the complete burner is removed, it is very easy to check the ignition electrode. First check if the distances
between the electrodes and between the electrode and the burner are according to the graph below. When these
are not correct, try to bend the electrodes in the right position. Notice: the electrodes undergo high temperatures,
therefore the electrodes become hard and are difficult to bend. While bending used electrodes they might break or
burst. Check the electrode, after bending, for any tear/crack and signs of rust. When they are burst/cracked or
rusty, replace the electrode. Also replace the electrode when there is a crack in the ceramic insulation of the elec-
trode. When the electrode is replaced, also the gasket should be renewed.
D = 8 - 10 mm
D = 0.315 - 0.393 inch D
3.5 mm / 0.14 inch
Burner door gaskets
Point of view in next picture
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