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

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S-CB
+
Boiler Range Manual
28
8.2 Air supply
When an air supply duct is connected from the outside of the building to the boiler, the boiler will operate as a
room-independent boiler (closed boiler).
The air supply duct can be made of:

PVC / PP

Thin-walled aluminium

Stainless steel
8.2.1 C
OMBUSTION AIR QUALITY
Combustion air must be free of contaminants. For example: chlorine, ammonia and/or alkali agents, dust, sand and
pollen. Remind that installing a boiler near a swimming pool, a washing machine, laundry or chemical plants does
expose combustion air to these contaminants.
8.2.2 A
IR SUPPLY THROUGH HUMID AREAS
When the supply duct will be placed in a boiler room with moist air (for example: greenhouses), a double walled
supply duct or an insulated duct must be used to prevent the possible condensation at the outside of the duct. It is
not possible to insulate the internal air pipes of the boiler and therefore condensation at the internal air canals must
be prevented.
When roof mounted, the air supply duct needs to be protected against rain, so no water will be entering the boiler.
8.3 Flue terminal
Never use aluminium (containing) flue gas materials for this boiler.
The flue terminal duct can be made of:

Stainless steel in combination with T120 gaskets

PP temperature class T120
Multiple boilers can be connected to a common duct. These flue gas systems for multiple boiler installations must
always be engineered as zero or negative pressure systems; this to prevent the risk of recirculation of the flue
gases. Consult the flue gas supplier for detailed information and engineering. See also the cascade manual for
these multiple boiler installations.
8.4 S-CB
+
60 Twin pipe version
The S-CB
+
60 boiler as shown in the picture below, is a twin pipe boiler with separate air inlet and flue
outlet pipes. Do NOT connect a concentric pipe to this boiler.
Note the sticker on the flue
pipe, indicating that this is
a twin pipe boiler.
The twin pipe version
is recognized by the
two pipes, one of
which has a
RED ring
cap.