Strebel S-CB Px 120, Руководство по установке, эксплуатации и техническому обслуживанию

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S-CB Px 120 Manual 26
8.
FLUE GAS DISCHARGE AND AIR SUPPLY SYSTEM
8.1. General
The boiler has a positive pressure flue system. The available combined pressure drop for the inlet and outlet sys-
tem
is 160 Pa.
Notice:
•
Install the horizontal flue components with a 3% fall in the direction of the boiler (about five centimetre for
every linear meter). When not installed accordingly it may result in condensation building up in the flue gas
tube which may cause component failure.
•
It is preferable to use roof terminals. Because of the high capacity, using wall terminals on the S-CB Px 120
can give unpleasant large flue gas clouds. When installed correctly, roof terminals in general give a better
flue gas dilution with the surrounding air, and a good transport away from the surroundings and the air inlet.
This is valid for concentric roof terminals and for a separate air inlet nearby a separate flue gas outlet.
•
When using a wall terminal, there is a risk of ice building-up on surrounding parts/structures, because the
condensate may freeze. This risk should be taken into account during the design phase of the heating instal-
lation.
Note.
The flue gas material should be fit for purpose, and comply with the applicable European standards. It must be
able to handle the condensate forming and transport, overpressure and must have a minimum temperature class
of
T120 .
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. Notice 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.
No water is allowed to enter the boiler through the air inlet canal at any time.
8.3. Flue terminal
Never use aluminium (containing) flue gas materials for this boiler.
The flue terminal duct can be made of:
•
Stainless steel of minimum temperature class T120
•
PP of minimum temperature class T120
The flue gas material should be fit for purpose, and comply with the applicable European standards.
It must be able to handle the condensate forming and transport, over pressure and must have a minimum tem-
perature class of
T120 .
Multiple boilers can be connected to a common duct. At all times, these flue gas systems for multiple boiler instal-
lations must 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.