40
INS
TALLER
U
SER
M
AINTEN
AN
CE
TECHNI
CI
AN
TECHNI
CAL
D
AT
A
C
12
C
≤
A
S
36
Key (Fig. 36):
A - Intake
C
- Minimum gradient 1.5
%
S - Exhaust
In the C(10) and C(12) installation, the boiler flue exhaust must be fitted with a Ø 80 flue gas non-return valve kit, consisting of the valve
itself with instructions, specification and relative sticker with additional safety information (Fig. 31):
Information for C10 installations
The boiler is suitable for operation in a C(10) system and only with the supply of methane gas (2H and 2E categories).
The boilers are developed to operate on collective pressurised flues with a safety pressure at the minimum heat input of 25 Pa and a safety
pressure at the maximum heat input of 100 Pa.
Calibration operations are not permitted in the boilers installed in type C(10) flue systems, as the CO2 emission levels are affect-
ed by the operating pressures induced in the collective flue, with particular reference to the minimum heat flow rate or any re-
circulation phenomena induced by the flue system.
The factory setting must be used in these flue systems, except for the “Min” parameter which must be set to 1.
The boiler must be connected to a flue system designed by a heating engineer in compliance with the local regulation in force.
The collective flue system must be suitably sized to allow the boiler to operate with the following specifications with which it was de-
signed:
- the maximum pressure, when n-1 boiler is working at maximum heat input (with n= number of total boilers connected or that can be
connected to the same collective duct), and a boiler works at minimum heat input, is 25 Pa;
- flue gas mass at maximum heat input;
- flue gas mass at minimum heat input;
- the minimum pressure difference allowed between the combustion product outlet and the combustion air inlet is -200 Pa (- 400 Pa for
C12) including -100 Pa (-300 Pa C12) of pressure generated by wind;
- the duct must have been sized with a nominal temperature of the combustion products of 25°C.
- the maximum allowed recirculation rate for wind action is 10%;
- the common flue must be certified to admit an overpressure of at least 200 Pa;
- no draught-breaker devices must be provided in the duct system.
In particular, at the coupling point to the pressurised collective flue, a plate must be visible showing at least the following technical infor-
mation:
- the name and trademark of the common flue gas pipe manufacturer;
- suitability to work with C(10) certified boilers;
- the maximum flue gas mass value allowed in kg/h;
- the dimensions of the common duct part;
The openings for combustion air and the inlet of combustion products of the pressurised collective flue must be closed and their
tightness must be checked when the boiler is disconnected.
The boiler connection to the pressurised collective flue must be made as instructed, without exceeding the specific maximum extensions
stated.
The boiler flue gas duct must be tilted a few degrees towards the boiler, to facilitate the evacuation of condensate.