20
3.2.9 80 mm diametre split duct
air/flue system (pic. 14 and pic. 15)
Installation types C12 – C32 -. C42-
C52- C82
RTFS 24 and CTFS 24
For installations with separate air intake
and flue gas discharge ducts the split
base kit (purchase code 0SDOPPIA03)
must be employed. The kit consists of the
following components (pic. 14A):
- no. 1 Ø 80 mm female stub pipe with
flange for connection to the flue gas
discharge pipe (flue gas deflector is inclu-
ded);
- no. 1 Ø 80 mm female stub pipe with
flange for connection to the air intake
pipe;
- no. 1 standard air deflector;
- fixing screws and seals.
WARNING
In case when a non-original split base kit is installed, the boiler will not be working properly.
Air intake
Minimum air intake duct length must be 1 meter.
Each wide radius 90° elbow (R=D) installed on the air intake duct is equal to 1 m linear length.
Each narrow radius 90° elbow (R<D) installed on the air intake duct is equal to 1.5 m linear length.
Load loss of the air intake terminal is not to be taken into consideration
.
The standard air deflector MUST be installed.
Flue gas system
Each wide radius 90° elbow (R=D) installed on the flue duct is equal to 1.5 m linear length.
Each narrow radius 90° elbow (R<D) installed on the flue duct is equal to 3.5 m linear length.
IMPORTANT
Flue pressure switch intervention
A flue pressure switch is fitted to the boiler. It operates proper flue gas dischar-
ge flow verification.
Should flue gas discharge and/or air intake system malfunction, the device
shuts down the boiler to prevent unsafe operation (see paragraph 1.2.4.3).
KIT 0SDOPPIA03
AIR
DEFLECTOR
FLUE GAS
DISCHARGE
STUB PIPE
pic. 14 A
AIR INTAKE STUB
PIPE
Pipe length (m)
Flue gas discharge
diaphragm
1 < L < 2*
Ø 40
2 < L < 15*
Ø 42
15 < L < 30*
Ø 45
30 < L < 38*
No diaphragm
* excluding the first elbow connected to the boiler
